JP2009504846A - Catalyst and process for selective hydroconversion of normal paraffins to lighter products rich in normal paraffins - Google Patents

Abstract

  The process and catalyst are suitable for hydroconverting heavy normal paraffins to lighter normal paraffin products while minimizing the formation of isoparaffins. The process and catalyst can be used for any feed containing heavy normal paraffins such as waxy lubricating fractions, crude wax or Fischer-Tropsch products. By selectively forming normal paraffin-rich products from heavy normal paraffins, the need for normal paraffin separation and purification processes can be reduced or eliminated.

Description

  This application claims the benefit of provisional application No. 60 / 706,513, filed Aug. 8, 2005.

  The present invention relates to a catalyst and a process for hydrogenating heavy normal paraffins to lighter normal paraffin products while minimizing the formation of isoparaffins.

C ₅₊ liquids that are high in normal paraffin are optimal for some applications.
-Solvents such as NORPAR (trademark)-Raw materials for ethylene production-Jet fuel and jet fuel blending components-Diesel fuel and diesel fuel blending components-Raw materials for linear alkylbenzene (LAB) production-biodegradable solvents-Lubricants Isomerization raw material for

Historically, C ₅₊ liquids rich in normal paraffins have been prepared by selectively extracting normal paraffins from mixtures such as petroleum. This treatment is relatively expensive and is limited to the content of normal paraffin in the raw material. Normal paraffin can also be produced by the Fischer-Tropsch process. However, the Fischer-Tropsch process also produces heavy products that can be outside the range of use for the above applications. When these heavy products are converted to lighter products by hydrocracking with conventional acidic catalysts, isoparaffin-rich products are obtained rather than normal paraffin-rich products.

  British Patent 2,146,350A, issued April 17, 1985, describes the production of high normal paraffin content diesel fuel by connecting the Fischer-Tropsch product to a hydrocracker. Is described. However, the high normal paraffin content in this patent is probably due to linear hydrocarbon compounds present in Fischer-Tropsch products boiling in the diesel range (normal paraffins, linear olefins, fatty acids and primary linear alcohols). by. These linear compounds are easily saturated and converted to normal paraffins. It was not clear that there was significant conversion of heavy materials to materials in the diesel boiling range, and that possibility is also low.

Witttenblink et al., US Pat. No. 5,807,413, issued September 15, 1998, describes a light density component having at least 80 +% by weight of n-paraffins, such as C _{5 to} C ₁₅ , preferably C _7. diesel engine fuel produced from a Fischer-Tropsch product wax by separating -C ₁₄ moiety is described. This patent describes how this product can be obtained directly from the Fischer-Tropsch process, but how it can be obtained by hydroconversion of heavier products. Not taught.

Selective degradation of heavy normal paraffins to lighter normal paraffins has been disclosed in the art. For example, G. E. Langlois, R.A. F. Sullivan and Clark J. et al. Egan, “Hydrocracking of Paraffins with Nickel on Silica-Alumina Catalysts-the Role of Cultivation”. Symposium on Titanium. The Division of the Petroleum Chemistry, American Chemical Society, Atlantic City Meeting, September 17-17, 1965 (Table 1, pages B-128) includes n-deformation with silica alumina using different metals during hydrogenolysis. Conversion of emissions _{(n-C 10)} have been described. Nickel without sulfidation gives a low iso / normal ratio (0.08) C ₄ -C ₇ product, but the conversion of this catalyst (7.8%) is very low and the methane yield (0 .28 wt%) is relatively high. In contrast, the nickel sulfide catalyst on silica-alumina has a high conversion (52.8) and a low methane yield (0.02 wt%), but a high iso / normal ratio (6.6) C ₄ ~ give the C ₇ product. Catalysts that combine good activity, low iso / normal ratio products and low methane production are not described.

  Jul A. Rabo, “Unifying Principles in Zeolitic Chemistry and Catalysis”, Zeolites: Science and Technology, edited by F. A. Ramoa Ribeiro et al., NATO ACS Series 80, 291-316, 1984 (295-296), describes the use of alkali neutralized zeolites without acidic hydroxyl to decompose hexane. However, this reference discloses cracking rather than hydroconversion and produces significant amounts of methane (3.1 wt%) and olefins.

Harry L. Coonradt and William E.M. Garwood, “The Mechanism of Hydrocracking”, I & EC Process Design and Development, Vol. 3, No. 1, January 1964, pp. 38-45, Hexadecane (n-C ₁₆ ), n- The use of platinum on silica-alumina catalyst to hydrocrack heptane and n-docosan (n-C ₂₀ , also known as eicosane) to produce low amounts of methane is described. Significant amounts of cycloparaffins are also produced and the product is isomerized (described on page 40, column 1), but the isomerization scale is not known. The pore properties of the support for this catalyst were not described, but were probably not microporous as indicated by the formation of cycloparaffins and isoparaffins.

B. S. Greensfelder, H.C. H. Voge and G.M. M.M. Good, "catalyst and the thermal decomposition of pure hydrocarbons (Catalytic and Thermal Cracking of Pure Hydrocarbons ) ", Industrial and Engineering Chemistry, 11 November 1949, the pages 2573-2584, for the conversion of cetane _{(n-C 16)} Evaluation of different catalysts is described. Of particular note is that activated carbon gives lower yields of methane than thermal reactions, but still produces significant amounts of methane, as well as significant amounts of ethane, propane and butane. It was noted that very small branching (isoparaffin formation) was observed (page 2576, column 2, second paragraph). However, as studies of other degradation, generated a significant amount of olefins, C 4 _- production of gas was over.

Hisato Asaoka, “borosilicate synthesis in non-aqueous solvents and it's activity for n-eicosane cracking”, J. Pp. 301-311, the preparation of borosilicate (“borolite-7”), which is not described as crystalline microporous material and appears to be amorphous, is disclosed. conversion to lighter products n-C ₂₀ is shown, not described as linear. The catalyst achieves n-C ₂₀ partial conversion at 900 ° F. and is free of Group 8 metals.

  Roberto Millini et al., “Synthesis and characterization of boron-containing molecular sieves”, Topics in Catalysis, 9, (1999), 13-34. Has been. On pages 16-17, an overview of the work of Taramasso et al. Producing B-ZSM containing less than 100 ppm of aluminum is shown. On pages 20-21, an overview of the work of Taramasso et al. Producing B-Beta containing less than 100 ppm of aluminum is shown. A summary of the catalytic activity of the boron molecular sieve is given on page 32. It is pointed out that the apparent contradiction in catalytic activity seen in previous studies was overcome when trace amounts of aluminum were clearly demonstrated to be sufficient to produce significant catalytic activity. . For example, 80-580 ppm Al in B-ZSM-5 was sufficient to produce interesting results in paraffin cracking, xylene isomerization, ethylbenzene dealkylation and cyclopropane isomerization. Zeolite containing only framework boron was not active in the same reaction. The reactions alleged to be active for boron zeolites without aluminum are described as olefin double bond isomerization, MTBE decomposition, aniline alkylation with methanol and cyclohexanone reorganization. The hydroconversion of heavy normal paraffins to lighter normal paraffins was not described.

According to the present invention, a hydrocarbon feed containing more than 5% by weight of C ₁₀₊ n-paraffins,
a. The temperature is 600 to 800 ° F,
b. Pressure is 50 to 5000 psig,
c. (1) a borosilicate or aluminoborosilicate molecular sieve containing at least 0.05% by weight boron and less than 1000 ppm by weight of aluminum, or a titanosilicate molecular sieve and (2) Provided is a process for producing a product of n-paraffin having a lower molecular weight than C ₁₀₊ n-paraffins in said feed by converting said feed in the presence of hydrogen by contacting with a catalyst comprising a group metal Is done.

The present invention also provides a hydrocarbon feed containing more than 5% by weight of C ₁₀₊ n-paraffins,
a. The temperature is 600 to 800 ° F,
b. Pressure is 50 to 5000 psig,
c. LHSV is 0.5 to 5,
d. Conversion rate from n-paraffin to smaller n-paraffin in raw material is 25% to 99%
In contact with a catalyst comprising (1) a borosilicate or aluminoborosilicate molecular sieve containing at least 0.05 wt% boron and less than 1000 ppm by weight of aluminum, or a titanosilicate molecular sieve and (2) a Group 8 metal. A process for producing an n-paraffin product having a lower molecular weight than C ₁₀₊ n-paraffin in the raw material by converting the raw material in the presence of hydrogen, from the n-paraffin in the raw material A method is provided wherein the selectivity to smaller n-paraffins is 60% or higher.

  The molecular sieve can contain less than 200 ppm by weight of aluminum, for example less than 20 ppm by weight. The Group 8 metal can be selected from the group consisting of Pt, Pd, Rh, Ir, Ru, Os and combinations thereof. Examples of molecular sieves include zeolite SSZ-13, SSZ-33, SSZ-46, SSZ-53, SSZ-55, SSZ-57, SSZ-58, SSZ-59, SSZ-60, SSZ-64, SSZ- 70, ZSM-5, ZSM-11, TS-1, MTT (for example, SSZ-32 and ZSM-23) and H-Y. The hydrocarbon feedstock can each contain less than 100 ppm sulfur and nitrogen.

  In one embodiment, the catalyst is exposed to sulfur prior to contacting the n-paraffin containing hydrocarbon feed.

Definitions As used herein, the following terms have the following meanings.

Hydroconversion, hydroconversion: operate at pressures above atmospheric pressure in the presence of hydrogen, minimize isomerization, and do not over form methane, _{C10 +} normal paraffins with lower molecular weight n-paraffins Catalytic method to convert to See the main features of the method described below. Hydroprocessing and hydrocracking are not only distinct catalytic processes, but also function at pressures above atmospheric pressure in the presence of hydrogen. Hydrocracking converts to a lighter product containing normal paraffin, a significant amount of isoparaffin. Hydroprocessing does not convert a significant amount of raw material into a lighter product, but removes impurities. In contrast, pyrolysis converts normal paraffins to lighter products with minimal branching, but pyrolysis does not use a catalyst. Pyrolysis typically operates at much higher temperatures to form more methane and produce a mixture of olefins and normal paraffins.

As shown in the table below, the current technology of n-paraffin selective hydroconversion can be distinguished from other cracking methods.

  Decomposition is the broadest term and refers to all methods and reactions that reduce their molecular weight by decomposing hydrocarbons into smaller components. Two types of methods, pyrolysis and catalytic cracking, do not use added hydrogen. Three types of processes, hydrocracking, hydrocracking, and current n-paraffin selective hydroconversion, use hydrogen.

  Among other factors, n-paraffin selective hydroconversion is a typical heat transfer by using hydrogen and the absence of significant amounts (greater than 1% by weight) of olefins in the product. And catalytic decomposition. The use of a catalyst and hydrogen is also a prominent feature.

  n-paraffin selective hydroconversion is distinguished from typical hydrocracking by the formation of paraffin-like products with lower iso / normal ratios. Previous studies have shown that the iso / normal ratio decreases when weaker acid hydrocracking supports are used, but these studies have demonstrated in the present invention, especially at high conversion levels. A low iso / normal ratio was not indicated.

  n-paraffin selective hydroconversion is distinguished from hydrogenation by the low methane yield (less than 1 wt%) when compared to that at high conversion.

  ppm values are expressed in weight unless otherwise specified.

  Isoparaffin / normal paraffin ratio (iso / normal ratio) refers to the weight ratio, unless otherwise specified.

  Molecular sieves are described in Donald W. Zoleite Molecular Sieves, Structure Chemistry and Use by Breck, John Wiley & Sons, 4-10, 1974. It includes zeolite, aluminophosphate (ALPO-11 etc.), silicoaluminophosphate (SAPO-11, SM-3 etc.), titanosilicate (TS-1, TS-2, SSZ-46 etc.) and other materials including.

  Zeolites are defined as molecular sieves containing silica at tetrahedral framework positions. Examples include, but are not limited to, silica (silicic acid) only, silica-alumina (aluminosilicate), silica-boron (borosilicate) and silica-titania (titanosilicate).

  Weakly acidic molecular sieves are zeolites containing less than 1000 ppm, such as less than 200 ppm or less than 20 ppm aluminum, and when combined with Pt, Pd, Rh, Ir, Ru, Os or combinations thereof, n-paraffin selective hydrogenation A conversion catalyst is formed.

  The catalysts useful in the present invention are not as strong as Si-Al zeolites, but have stronger acidity than silanol groups in all total Si zeolites. This type of catalyst is defined herein as having weak acidity.

“Weakly acidic” is used herein to refer to Corma et al. Am. Chem. Soc. 116, No. 1, 1994, pages 136-142, following a set of related structures of fixed geometry (eg, Si—O—Al, Si—O—Ga, It is defined by calculating the frontier orbital energy for bridging oxygen atoms in (Si—O—B, Si—O—Si). Frontier orbital energy is calculated from E _LUMO and E _HOMO energies and is shown in Table IV of Corma et al. Table IV does not describe the value for Si-O-Si, but it is individually estimated to exceed the value of 7.44 described in Table IV. The main point in this table is that as the acid strength increases (Si—O—B to Si—O—Al), the value of the frontier orbital energy decreases.

  Charge balanced systems, such as all silica systems, are very weak in acidity, and cross-linked silanols have high energies in excess of 7.44 eV. The strongly acidic Si—O—Al system has a lower energy of 7.13 eV.

Materials useful for the catalyst employed in the present invention are:
Greater than the energy for Si-O-Al,
Preferably, 0.1 eV greater than the energy for Si—O—Al,
-More preferably, it is 0.25 eV greater than the energy for Si-O-Al,
Most preferably, it will have a frontier orbital energy that is 0.25 eV greater than the energy for Si-O-Al and less than the energy for Si-O-Si.

  Many other procedures for measuring or calculating solid acidity have appeared in the literature for several years. These include different calculation procedures, the use of gas adsorbents, and changes in the color of the dye in solution. These techniques may have other uses, such as in the control of catalyst production, but they should not be used in place of the methods described above.

An n-paraffin selective hydroconversion catalyst converts 80% of n-C ₁₆ at the conditions set forth in Example 1 and at temperatures below 800 ° F., eg, below 700 ° F. or below 600 ° F. , less than 0.75, such as less than 0.2, a catalyst to give the _{C 6} products having iso / normal ratio, or less than 0.01 less than 0.05. Details are shown in Table 3 and Example 1.

  The pore size and number of dimensions of the molecular sieve. A molecular sieve is a crystalline material with regular passages (pores). When examined against several unit cells of the structure, the pores form an axis based on the same units in the repetitive crystal structure. The overall path of the pores is along the pore axis in the unit cell, but the pores may be branched from the axis, even if the dimensions are expanded (to form a cage) Alternatively, it may be narrowed. The axis of the pore is often parallel to one of the crystal axes. The narrowest position along the pore is the pore opening. The pore size refers to the size of the pore opening. The pore size is calculated by counting the number of tetrahedrons that form the periphery of the pore mouth. A pore having ten tetrahedral positions at its pore mouth is usually called a ten-ring pore. The pores associated with catalysis in this application have a pore size of 8 or more rings. A molecular sieve is called one-dimensional when it has only one type of associated pore with the same orientation of the axis relative to the crystal structure. The molecular sieve may have differently structured pores or may have the same structure but be oriented with more than one axis associated with the crystal. In these cases, the number of dimensions of the molecular sieve is determined by adding the number of related holes with the same structure and different axes with the number of related holes of different shapes.

The procedure for obtaining the pore size and the number of dimensions is as follows. Table 6 is a first reference, and these properties are listed in the row labeled as sieve structure. PtB / ZSM-5 is described as 3D10R meaning that it is a three-dimensional molecular sieve with only 10 ring holes. Pt / B-SSZ-33 is described as 12 / 10R3D which means it is a three-dimensional molecular sieve with 10 and 12 ring holes. If the structure is not described in Table 6, the following reference: Atlas of Zeolite Structure Types, Ch. Baerlocher, W.M. M.M. Meier and D.M. H. Reference is made to Olson, 5th revised edition, 2001. The pore size and dimensionality of different molecular sieves are described in Channels. This is summarized in Table 3 on pages 12-15 of this reference. The number of different pores for each pore is described, and the number of dimensions is determined by adding the number of stars. Pore dimensions are shown in bold. For example, ZSM-57 (MFS structure) is described as [100] 10 5.1 × 5.4 ^* ← → [010] 83.3 × 4.8 ^* . The number of dimensions is 2, which is the total number of stars. There are two types of pores, 10 rings and 8 rings. The numbers [100] and [010] refer to the orientation of these pore axes relative to the crystal axis.

  If the structure is not described in Table 6 or Atlas of Zeolite Structure Types, the crystal structure is determined, and the pore size and the number of dimensions are determined using the above general analysis.

  A microporous molecular sieve is defined as having 20 or fewer holes.

  Group 8 and the periodic table are defined in the inner and front covers of CRC Handbook of Chemistry and Physics, 49th edition. Group 8 refers to elements in a row starting with Fe, Co, and Ni.

  Crude wax is a by-product from lubricating oil production. A waxy 600 ° F. + hydrocarbon material from a synthetic source such as petroleum or Fischer-Tropsch process is dewaxed with a solvent by conventional methods to form a dewaxed lubricating base oil and a waxy crude wax byproduct.

  Hydrocarbon feedstock, material or product: a pure compound or mixture of compounds containing H, C and optionally S, N, O and other atoms. Examples include crude feeds, synthetic crude feeds, intermediate streams, gasoline, jet fuel, diesel fuel, petroleum products such as lubricating base oils, and alcohols such as methanol and ethanol.

  Hydrocarbon assets: Materials containing H, C and optionally S, N, O and other elements used to produce hydrocarbon products. Examples of assets are natural gas, methane, coal, petroleum, tar sand, oil shale, shale oil, plastic waste, tire waste, municipal waste, derivatives and mixtures thereof.

  Fischer-Tropsch method: This is described in US Patent No. 6,392,108 issued May 21, 2002 to O'Rear. It is a process for converting synthesis gas to a hydrocarbon product.

  Syngas (or synthesis gas): A gas mixture containing carbon monoxide (CO) and hydrogen, and optionally other components such as water and carbon dioxide. Sulfur and nitrogen and other heteroatomic impurities are undesirable because they can contaminate downstream of the Fischer-Tropsch process. These impurities can be removed by conventional techniques.

Syngas generator: (Syngas generation is described in U.S. Pat. No. 6,992,114 issued January 31, 2006, which is incorporated herein by reference. ). This is a method or procedure for producing syngas from hydrocarbon assets. The syngas generator can be a light hydrocarbon reformer or heavy hydrocarbon reformer that uses methane or natural gas as a feedstock. The reforming includes various techniques such as steam reforming, partial oxidation, dry reforming, series reforming, convective reforming and autothermal reforming. Both have in common the production of syngas from methane and oxidants (steam, oxygen, carbon dioxide, air, concentrated air or combinations). The gas product typically contains some carbon dioxide and steam in addition to the syngas. Series reforming, convective reforming and autothermal reforming employ two or more syngas type reactions to improve the utilization of heat of reaction. Methods for producing synthesis gas from C ₁ -C ₃ alkanes are well known in the art. Steam reforming is typically preferred at temperatures from about 1300 ° F. (705 ° C.) to about 1675 ° F. (913 ° C.) and pressures from about 10 psia (0.7 bar) to about 500 psia (34 bar). It is done by a C ₁ -C ₃ alkane in the presence of a reforming catalyst into contact with the steam. Suitable reforming catalysts that can be used include, for example, nickel, palladium, nickel-palladium alloys, and the like. Regardless system for producing syngas, any sulfur compounds contained in the C ₁ -C ₃ alkane feedstock, for example, be removed hydrogen sulfide and mercaptans desirable. It can influence this by passing the C ₁ -C ₃ alkane gas to the packed bed sulfur scrubber containing zinc oxide bed or other slightly basic packing material. If the amount of C ₁ -C ₃ alkane exceeds the capacity of the synthesis gas apparatus, the surplus C ₁ -C ₃ alkane can be utilized to provide energy to the entire facility. For example, C ₁ -C ₃ alkanes can be burned in a steam boiler to provide steam used in the pyrolysis process.

In a heavy hydrocarbon reformer, the method includes converting coal, a heavy oil feedstock such as residual oil, or a combination thereof to syngas. The temperature in the reaction zone of the syngas generator is about 1800 ° F. to 3000 ° F. and the pressure is about 1 to 250 atmospheres. The atomic ratio of free oxygen in the oxidizer to carbon in the raw material (O / C, atoms / atom) is about 0.6 to 1.5, preferably about 0.80 to 1.3. The free oxygen-containing gas or oxidant may be air, oxygen-rich air, ie greater than 21 mol% to 95 mol% O ₂ , or a substantially pure acid, ie greater than 95 mol% O _2. Good. The exhaust gas stream exiting the partial oxidizer is generally H ₂ : 8.0 to 60.0; CO: 8.0 to 70.0; CO ₂ : depending on the amount and composition of the feed gas stream. 1.0 to 50.0, H ₂ O: 2.0 to 75.0, CH ₄ : 0.0 to 30.0, H ₂ S: 0.1 to 2.0, COS: 0.05 to 1 0.0, N ₂ : 0.0 to 80.0, Ar: 0.0 to 2.0 mol% composition. Particulate matter entrained in the exhaust gas stream may generally contain about 0.5 to 30% by weight or more, especially about 1 to 10% by weight of particulate carbon (basic weight of carbon in the feed to the gas generator). . Fly ash particulate material may be present with particulate carbon and molten slag. Conventional gas scrubbing and / or purification steps can be employed as described in US Pat. No. 5,423,894 issued to Child et al., June 13, 1995.

  Syngas can also be produced by direct conversion of underground hydrocarbon assets. Karanika et al., US Pat. No. 6,698,515, issued March 2, 2004, describes an example for converting underground (or in situ) hydrocarbon assets.

Measurement of normal paraffins in the measurement wax-containing samples of normal paraffins in the wax sample, the detection limit of 0.1 wt%, is necessary to use a method in which the individual C ₇ to measure the content of C _{110 n-paraffins} is there. The preferred method used is as follows.

  Quantitative analysis of normal paraffin in wax is measured by gas chromatography (GC). The GC (Agilent 6890 or 5890 equipped with a capillary split / non-split inlet and a flame ionization detector) is equipped with a flame ionization detector that is highly sensitive to hydrocarbons. The process used a methylsilicone capillary column routinely used to separate hydrocarbon mixtures by boiling point. The column was fused silica with 100% methyl silicone, 30 meters long, 0.25 mm ID, 0.1 micron film thickness supplied by Supelco. Helium is the carrier gas (2 ml / min) and hydrogen and air are used as flame fuel.

Melt the wax to obtain a 0.1 g homogeneous sample. The sample is directly dissolved in carbon disulfide to obtain a 2 wt% solution. If necessary, the solution is heated until visually clear and free of solids and then poured into the GC. Heat the methylsilicone column using the following temperature program.
Initial temperature: 150 ° C. (when C _{7 to} C ₁₅ hydrocarbons are present, the initial temperature is 50 ° C.)
・ Gradient: 6 ℃ per minute
-Final temperature: 400 ° C
・ Final hold: 5 minutes or until peak no longer elutes

  The column then efficiently separates as the number of carbons increases from non-normal paraffin to normal paraffin. A known control is analyzed in the same manner to determine the elution time of a specific normal paraffin peak. The standard used is an ASTM D2887n-paraffin standard purchased from a vendor (Agilent or Supelco) spiked with 5 wt% polywax 500 polyethylene (purchased from Petrolite Corporation, Oklahoma). The standard is melted prior to injection. Historical data collected by control analysis also guarantees the resolution efficiency of the capillary column.

  When present in the sample, the normal paraffin peak is well separated and easily distinguishable from other types of hydrocarbons present in the sample. Those peaks that elute outside the residence time of normal paraffins are called non-normal paraffins. All samples are integrated using baseline hold from start to end. N-paraffin is skimmed from the entire area and accumulated from valley to valley. All detected peaks are normalized to 100%. HP Chemstation was used for peak identification and calculation of results.

  Measurement of B, Al and Si in zeolites and solid reagents: Elemental analysis is performed by ICP-OES following digestion of the material by HF digestion in a Teflon beaker. The detection limit of B in the HF solution is 0.1 ppb, and the detection limit of Al is 0.2 ppb. ICP-OES technology is described in Willard, Merritt, Dean and Settle; Instrumental Methods of Analysis, 7th edition. This is interpreted as a detection limit of about 10 ppm of aluminum in the original material, assuming sufficient material (at least 1 gram) is dissolved. A preferred method is to measure the components in a synthetic sample that requires at least 1 gram of material. However, if the available sample size is less than 1 gram, as in the case of a small survey sample, measure traces of aluminum in the components (silica reagent, boron reagent, water, etc.) and all are end products The maximum amount of aluminum in the sample can be calculated.

In this study, the aluminum content of the reagents used in this study was as follows:
Tetraethylorthosilicate (TEOS) Not detected Cab-O-Sil 18ppm
Deionized water not detected NH ₄ NO ₃ not detected Na ₂ B ₄ O ₇ described in the examples

  The aluminum content of weakly acidic molecular sieves produced in this study without intentional addition of aluminum is less than 20 ppm.

Measurement of sulfur and nitrogen in raw materials:
For samples with a pour point less than 50 ° C., the nitrogen content in the sample is measured by the following procedure. Dilute 0.2-2.0 g parts of sample using solvent. Ten microliters of diluted sample is injected into the quartz boat present in the carrier gas stream. The boat is gradually transferred into the combustion furnace and the diluted sample evaporates. The volatilized sample gas mixes with oxygen in a high temperature furnace and burns, producing nitric oxide (NO), among other gases. The gas is dried, sent to the detection cell, and mixed with ozone. Ozone reacts with NO and chemiluminescents in the process. Light is detected and converted to voltage to obtain the peak area for each sample. A standard is used to relate area to concentration. Results are reported as nitrogen ppm. Detailed test methods can be found in ASTM D4629.

For a sample containing less than 1000 ppm sulfur and having a pour point less than 50 ° C., the sulfur content is measured by the following procedure. About 10 microliters of sample is volatilized and mixed with oxygen at a temperature of 1000 ° C. to oxidize the sulfur to sulfur dioxide SO ₂ . The water product during sample combustion is removed, and then the sample combustion gas is exposed to UV light. SO ₂ absorbs energy from UV light and is converted to excited SO ₂ ^* . The fluorescence emitted from the excited SO ₂ ^* is detected by the photomultiplier tube when returning to the steady state SO ₂ and the resulting signal is a measure of the sulfur contained in the sample. Detailed test methods can be found in ASTM D5453. For samples containing more than 1000 ppm sulfur, the sulfur content is measured by XRF.

  For samples with a pour point of 50 ° C. or higher, especially samples by the Fischer-Tropsch method, a preferred method for measuring heteroatom content is described in Maleksadeh US Pat. No. 6,503, issued Jan. 7, 2003. , 956.

We have discovered catalysts that can be used to hydroconvert heavy normal paraffins to form C ₅ + normal paraffins. The main features of the catalyst are as follows.
A Group 8 metal (eg Pt) optionally exposed to sulfur.
-A microporous weakly acidic molecular sieve without a strong acid function, preferably without a combination of silicon and aluminum. The microporous weakly acidic molecular sieve can be composed of a siliceous skeleton such as zeolite, and the weakly acidic molecular sieve is preferably zeolite and contains 12 or fewer rings, for example, 10 or fewer rings. Weakly acidic molecular sieves contain a second oxidizing element (silica first) that does not induce strong acidity, but acts to promote hydroconversion. For example, the second oxide element is boron or titanium, most preferably boron.
• Defined activity and product selectivity for the conversion of n-C ₁₆ at standard conditions.
It may be advantageous to expose the catalyst to sulfur before carrying out the n-paraffin hydroconversion. This pre-contact can be effected by the use of hydrogen sulfide or light sulfur-containing compounds such as dimethyl sulfide and dimethyl disulfide. Alternatively, feedstocks containing greater than 1 ppm sulfur, such as greater than 10 ppm sulfur, can be treated with a catalyst prior to n-paraffin hydroconversion. A low sulfur feed containing n-paraffins can then be hydroconverted using a sulfurization catalyst.
It was also found that a catalyst useful in the present invention can be identified by performing a simple test using n-C ₁₆ as a raw material. A catalyst comprising at least one molecular sieve and at least one Group 8 metal is tested by placing 0.5 g of the catalyst in a 1/4 inch inner diameter tubular reactor. The catalyst converts at least 80% of n-hexadecane at a pressure of 1200 psig, in the presence of hydrogen at a flow rate of 160 ml / min, with an n-hexadecane feed rate of 1 ml / hour, at a temperature below 800 ° F. 2) The catalyst passes the test and is considered useful for the present invention if it produces a product comprising C ₆ hydrocarbons having an iso / normal weight ratio of less than 0.75.

The characteristics of the n-paraffin selective hydroconversion process include the following characteristics.
• Raw material containing more than 5 wt% _{C10 +} normal paraffin, preferably more than 50 wt% _{C10 +} normal paraffin, most preferably more than 80 wt% _{C10 +} normal paraffin. Suitable sources of feedstock are derived from petroleum products and synthetic crude feedstocks. Crude wax and Fischer-Tropsch products are preferred raw materials.
• The raw material may contain low amounts of sulfur and nitrogen (see table of preferred properties below).
The feedstock may contain low amounts of oxygen, in particular less than 1% by weight, for example less than 1000 ppm by weight or less than 100 ppm by weight.
-The raw material can be purified by hydrotreatment prior to hydroconversion.
The pressure is from 50 to 5000 psig, such as from 100 to 2000 psig, or from 250 to 1000 psig.
LSHV is preferably 0.5 to 5, for example 1 to 2 LHSV.
The temperature is 600 to 850 ° F., for example 700 to 800 ° F. or 725 to 775 ° F.
-If the process is carried out continuously, the conversion of heavy paraffin in the feed per pass is 25 to 99%, for example 50 to 80% or 60 to 75%.
C ₅₊ normal paraffin product is separated from any non-converted feed, for example by distillation.
• Performance is improved if the catalyst is exposed to sulfur prior to contacting the feed to be hydroconverted.

Molecular sieves Examples of molecular sieves useful for the n-paraffin selective hydroconversion of the present invention include SSZ-13, SSZ-33, SSZ-46, SSZ-53, SSZ-55, SSZ-57, SSZ-58, SSZ. -59, SSZ-64, ZSM-5, ZSM-11, TS-1, MTT (eg SSZ-32 and ZSM-23 etc.), HY, SSZ-60 and SSZ-70 But not limited to. Note that each of these molecular sieves is a microporous molecular sieve as defined above, containing silicon as the main tetrahedral element, having 8 to 12 ring pores. In order to be useful as an n-paraffin selective hydroconversion catalyst, they contain low amounts of strongly acidic components (such as aluminum), weakly acidic components (such as boron or titanium), such as platinum. Must be complex with any Group 8 metal.

Molecular sieve SSZ-13 is disclosed in US Pat. No. 4,544,538 issued to Zones, issued Oct. 1, 1985.
Molecular sieve SSZ-33 is disclosed in US Pat. No. 4,963,337 issued Oct. 16, 1990 to Zones.
Molecular sieve SSZ-46 is disclosed in US Pat. No. 5,968,474 issued October 19, 1999 to Nakagawa et al.
Molecular sieve SSZ-53 is disclosed in Elomari US Pat. No. 6,632,416 issued Oct. 14, 2003.
Molecular sieve SSZ-55 is disclosed in US Pat. No. 6,475,463 issued to Elomari et al.
Molecular sieve SSZ-57 is disclosed in Elomari US Pat. No. 6,544,495, issued April 8, 2003.
Molecular sieve SSZ-58 is disclosed in Elomari US Pat. No. 6,555,089, issued April 29, 2003.
Molecular sieve SSZ-59 is disclosed in Elomari US Pat. No. 6,464,956, issued on Oct. 15, 2002.
Molecular sieve SSZ-64 is disclosed in Elomari US Pat. No. 6,569,401, issued May 27, 2003.
Molecular sieve ZSM-5 is disclosed in U.S. Pat. No. 3,702,886 issued to Argauer et al.
Molecular sieve ZSM-11 is disclosed in Chu, U.S. Pat. No. 3,709,979, issued Jan. 9, 1973.
Molecular sieve TS-1 is disclosed in US Pat. No. 4,410,501 issued Oct. 18, 1983 to Taramasso et al.
Molecular sieve MTT is disclosed in US Pat. No. 5,053,373 issued October 1, 1991, US Pat. No. 5,252,527 issued October 12, 1993, 1978. U.S. Pat. No. 4,076,842 issued to Feb. 8 by Plank et al.
Molecular sieve Y is disclosed in Breck, U.S. Pat. No. 3,310,007, issued April 21, 1964.
Molecular sieve SSZ-60 is disclosed in Elomari US Pat. No. 6,620,401 issued September 16, 2003 and Elomari US Pat. No. 6,540,906 issued April 1, 2003. It is disclosed.
Molecular sieve SSZ-70 is disclosed in published U.S. Patent Application No. 20060140855 A1, published June 29, 2006.
Each of the above patents and patent applications is hereby incorporated by reference in its entirety.

Preparation of catalyst Synthesis of microporous weakly acidic molecular sieve Fine porous weakly acidic molecular sieve from a mixture containing an inorganic reagent, water, optionally an organic structure inducer (typically an amine) and optionally an inorganic base (NaOH, KOH, etc.) Can be synthesized. This synthesis is well known in the art and is widely practiced commercially. It is typically carried out over several days in a stirred autoclave operating at a pressure above atmospheric pressure. The product of the synthesis is recovered by filtration, centrifugation and other techniques. The microporous weakly acidic molecular sieve product is washed to remove impurities. A feature of the present invention is the selection of reagents to avoid introducing a strong acid function into the microporous weakly acidic molecular sieve. In particular, aluminum should be avoided in the synthesis of silica-based microporous weakly acidic molecular sieves such as borosilicate. Aluminum in the water can be suppressed by purification such as ion exchange. Aluminum in the inorganic reagent can be suppressed by selecting the reagent. For silica-containing reagents, the aluminum content should be as low as possible, ie less than 500 ppm by weight, preferably less than 100 ppm by weight, and most preferably less than 20 ppm by weight. An example of a low aluminum silica-containing reagent is CAB-O-SIL M5® (fused silica) containing 4 to 24 ppm by weight of aluminum (obviously depending on the batch). Aerosil 200 fused silica is another source of silica containing less than 20 ppm by weight of aluminum. Another example is tetraethyl orthosilicate containing less than 0.2 ppm by weight of aluminum. Examples of materials containing excess aluminum (for purposes of the present invention) include Ludox AS-40 (typically containing 1000 ppm by weight of aluminum), as well as issued on July 5, 1988. U.S. Pat. No. 4,755,279 issued to Unmuth et al. And U.S. Pat. No. 4,728,415 issued March 1, 1988 to Nalco 2327. An analysis of the aluminum content of typical silica reagents is published in Microporous and Mesoporous Materials, 32 (1999), pages 119-129. Aluminum impurities in these reagents impart excessively strong acidity at high levels. Since aluminum tends to concentrate in the microporous weakly acidic molecular sieve product, the 500, 100 and 20 weight ppm limits for the silica reagent are less than 1000 ppm, preferably 200 ppm by weight for the microporous weakly acidic molecular sieve. To an aluminum limit of less than, most preferably less than 20 ppm by weight. Zones et al., US Pat. No. 5,166,111, issued Nov. 24, 1992, describes the preparation of boron beta microporous weakly acidic molecular sieves according to the present invention.

Formation of the catalyst component In order to be used in commercial applications, the catalyst component must be formed to a size suitable for use. The formed catalyst should have at least one dimension greater than 50 microns, preferably greater than 1/50 ", most preferably greater than 1/20". This formation can be performed by techniques such as pelletization, extrusion and combinations thereof. Extrusion is the preferred method. The extruded material can have a cylindrical shape, a trilobal shape, a groove shape, or other axisymmetric shape that facilitates diffusion and access to the inner surface. A binder is typically used to assist in the formation of a catalyst with good physical strength.

Binder When preparing the catalyst used in the present invention, a microporous weakly acidic molecular sieve is bound. They are preferably combined with a matrix material that is resistant to temperature and other conditions employed in hydrocarbon conversion processes. It is also preferable to use a matrix material that does not impart strong acidity to the catalyst. The matrix material can include active and inactive materials. In order to improve the crushing strength of the catalyst, a binder is often added. The choice of binder and binding conditions depends on the microporous weakly acidic molecular sieves and their intended use.

  The binder material can be selected from among the refractory metal oxides of Groups 4A and 4B of the Periodic Table of Elements. Particularly useful are oxides of silicon, titanium and zirconium, with silica, particularly low aluminum silica being preferred. Combinations of the oxide and other oxides are also useful. For example, use silica-magnesia, silica-zirconia, silica-tria, silica-beryllia, silica-titania, titania-zirconia and silica-magnesia-zirconia on the assumption that these combinations do not form strongly acidic materials. (In contrast, the silica-alumina binder of U.S. Pat. No. 4,728,415 used for borosilicate materials will impart strong acidity). These oxides can be crystalline or amorphous or can take the form of gelatinous precipitates, colloids, sols or gels. Silica in the form of a silica sol is a preferred binder. A preferred silica sol has about 30% by weight silica, contains small particles (7-9 mm in diameter), and provides a catalyst with good wear resistance and excellent crush strength.

  Formation of pellets or extrudates with molecular sieves including microporous weakly acidic molecular sieves useful in the present invention generally involves the use of extrusion aids and viscosity modifiers in addition to the binder. These additives are typically cellulosic materials such as Dow Chemical Co. Organic compounds such as Methocel®, ethylene glycol and stearic acid sold by Many such compounds are known in the art. It is important that these additives do not leave a detrimental residue after pelleting, i.e. a residue with undesirable reactivity or a residue that can block the pores. In the present invention, it is particularly desirable that the residue does not produce a strong acid function on the catalyst. The cleaning will remove low amounts of these materials. The residue of the extrusion aid is preferably less than a sufficient few percent, more preferably less than 0.1% by weight.

  Methods for preparing catalyst compositions are well known to those skilled in the art and include conventional techniques such as spray drying, pelletizing, extrusion and various sphere manufacturing techniques. The zeolites described in Miller U.S. Pat. No. 5,558,851 issued September 24, 1996 and Miller U.S. Pat. No. 5,514,362 issued May 7, 1996. Newly developed methods of forming extrudates for the binder can also be used. The entire contents of these patents are incorporated herein by reference.

  The relative ratio of molecular sieve to binder / matrix can vary widely. Generally, the molecular sieve content ranges from about 1 to about 99 weight percent of the dry composite, more commonly from about 5 to about 95 weight percent, typically 50 to 85%.

  Although not required for experimental applications, bound microporous weakly acidic molecular sieves are probably required for full-scale commercial applications of the present invention. It is preferred to use the entire extrudate for commercial applications rather than a milled extrudate or unbound microporous weakly acidic molecular sieve. The bound microporous weakly acidic molecular sieve reduces the pressure drop through the reactor, improves the flow rate, and is easy to fill and withdraw.

Modification If the synthetic microporous weakly acidic molecular sieve or the combined microporous weakly acidic molecular sieve is found to have excessively strong acidity, this function can be eliminated by the modification method. Suitable reforming methods include acid extraction (typically with HCl), steam treatment, treatment with ammonium fluorosilicate, and combinations thereof. All treatments should preferably be performed with a microporous weakly acidic molecular sieve at a concentration, temperature and time sufficient to remove excessively strong acidity without significant loss of structure or pore volume (determined by XRD). Contact with aqueous solution or steam.

The Group 8 metal catalyst comprises at least one Group 8 metal, preferably a noble metal (Pt, Pd, Rh, Ir, Ru, Os), more preferably platinum. The metal content is preferably 0.1 to 5 wt%, more preferably 0.1 to 3 wt%, most preferably 0.3 to 1.5 wt%, based on the weight of the microporous weakly acidic molecular sieve. %. Platinum compounds that form positively charged platinum complex ions in solution are preferred platinum sources. Particularly preferred are platinum tetraamine chloride and nitrate.

  One or more kinds of metals other than Group 8 such as tin and indium and Group 7B metals such as rhenium can be added to these Group 8 metals. Examples include Pt / Sn, Pt / Pd, Pt / Ni and Pt / Re. A variety of known and conventional techniques such as ion exchange, incipient wetting, pore filling, impregnation, etc. can be employed to easily introduce these metals into the composite. Care should be taken that Group 8 metals, such as platinum, are introduced in a manner that provides excellent uniform dispersion. An initial wet impregnation method is preferred.

Reactor The feed can be contacted with the catalyst in a fixed bed system, moving bed system, fluidized system, batch system, or combinations thereof. A reactor similar to the reactor employed for hydrotreating and hydrocracking is preferred. Both fixed bed systems and moving bed systems are preferred. In a fixed bed system, the preheated feed is fed into at least one reactor containing a fixed bed of catalyst. The feed flow can be upward, downward or radial. The reaction is an exothermic reaction, especially when the content of heavy paraffin is high (greater than 50% by weight) and the conversion is high (greater than 50%), interstage cooling may be required. This cooling can be carried out by injection of cold hydrogen between the reaction beds. The reactor must be equipped with instruments for monitoring and controlling the temperature, pressure and flow rate typically used in hydrocracking equipment.

Product Recovery and Subsequent Treatment The effluent from the hydroconversion reaction zone can be separated into the desired stream or portion. Products such as solvents, jet fuel, jet fuel blending components, diesel fuel, diesel fuel blending components, raw materials for the production of linear alkylbenzenes, raw materials for the production of lubricating base oils and by-product gases, such as distillation It can be recovered using conventional techniques. Normal paraffin solvent can be recovered from the product. If the n-paraffin content is not sufficient, it can be increased by using well-known adsorption techniques. One commercial adsorption method for removing branched hydrocarbons and aromatics from linear paraffins is McPhee, Petroleum Technology Quarters, pages 127-131, the description of which is incorporated herein by reference. (Winter 1999/2000), known as the Molex or Solvex method. This separation technique works by selectively adsorbing normal paraffin. However, the products from n-paraffin selective hydroconversion are rich in normal paraffins and contain very little other species. Therefore, it is preferable to use an adsorbent having selectivity for adsorbing branched species from normal paraffin. Such materials are described in Santili D., which is incorporated herein by reference. S. Harris T .; V. Zones S. I. , Microporous Mater. , 1329, 1993, described as reverse shape selection. Other subsequent processing and integration options are described below.

Example 1 n-C ₁₆ Test of Hydroconversion Catalyst The hydroconversion of n-hexadecane is tested to identify catalysts that give a higher selectivity of lighter normal paraffin products over isomerization products. These results can be expected that those of value in selecting the useful catalysts, e.g. n- paraffin selective hydroconversion catalysts for n- paraffins hydroconversion to C ₁₀ or more molecules.

  Unless otherwise specified in a specific embodiment, introduction of noble metal (Pt or Pd) is performed by ion exchange at 212 ° F. for a minimum of 5 hours, followed by filtration, washing, drying, and firing at 900 ° F. It was.

  Test conditions were 1200 psig total pressure, 160 ml / min downflow hydrogen (when measured at 1 atm and 25 ° C.), 1 ml / hr downflow liquid feed, and alundum to preheat the feed. Of stainless steel reaction tube with an outer diameter of 1/4 inch, packed in the upstream of the catalyst and filled in the center of 3 feet in length (the catalyst is located in the center of the tube) And extends about 1 to 2 inches in length). Initially, all materials were reduced overnight in flowing hydrogen at 570 ° F.

The product was analyzed by on-line capillary GC once every 30 minutes. Raw data from the GC was collected by an automated data collection / processing system and conversion and selectivity were calculated from the raw data. The catalyst was first tested at 600 ° F. to determine the temperature range for the next stage measurement. The temperature was adjusted to give a conversion of less than 80%. Then, the temperature was raised by 10 ° F. until the conversion rate exceeded 80%. During the test, the temperature was raised gradually and 8 online samples were collected at each temperature (over 4 hours). Since conversion was defined as the conversion of n-C ₁₆ to a product with less than n-C ₁₆ carbons, iso-C ₁₆ was not counted as a conversion product. Yields were expressed as weight percent of materials other than n-C ₁₆ and iso-C ₁₆ included as product.

  If the catalyst is to qualify as a catalyst of the present invention, when tested in this way, at least 80% of the hexadecane will be at a temperature of 800 ° F. or lower, such as 700 ° F. or lower. Alternatively, it must be converted to a product having 15 or less carbon atoms at a temperature of 600 ° F or lower.

Also, if the catalyst is used at a temperature that results in 80% conversion of hexadecane to a product having 15 or less carbon atoms, even under these conditions, the iso / normal ratio of the C ₆ product is 0. Less than .75, such as less than 0.2, less than 0.05, or less than 0.01.

Preferably, the catalyst 80% conversion of the above, also less than 2, for example, give the _{C 13} iso / normal ratio of less than or less than 0.1 0.5.

Results are obtained at 80% conversion. However, if data at 80% conversion cannot be obtained accurately, the result at 80% conversion can be obtained by linearly interpolating the result of conversion slightly around 80%. Results in conversions before and after 80% conversion are obtained as close to 80% conversion as possible to ensure that linear interpolation is appropriate. To confirm that linear interpolation is accurate, the temperature and the corresponding conversion, should the absolute value of the percentage difference between the high and low values of C ₆ iso / normal ratio is selected so as not to exceed 40% It is.

Percentage difference = absolute value of {100 * [(high C ₆ iso / normal ratio−low C ₆ iso / normal ratio) / low C ₆ iso / normal ratio]} In this calculation, the low value of the C ₆ iso / normal ratio If is 0, the percentage difference is reported as 0 and the resulting linear interpolation is appropriate.

This test can be used to determine if a strong acid function was introduced into the catalyst during preparation. For example, when comparing the binding material and unbound materials, the increase in a significant decrease or C ₆ iso / normal ratio of the activity in the binding material may be indicators of introducing acidic.

Example 2-Preparation and Testing of Pt / B-ZSM-5 ZSM-5 is a three-dimensional zeolite in which all pores are composed of a 10-ring structure. A sample of boron-ZSM-5 was prepared in hot water according to the following procedure. In a 23 cc Teflon liner, 2.5 g of 25% by weight aqueous solution of tetrapropylammonium hydroxide, 1.25 g of 1N NaOH, 8 g of deionized water and 0.06 g of sodium borate decahydrate. Mix thoroughly until the sodium borate is completely dissolved. To this mixture was added CAB-O-SIL M-5 ( fused silica -98% SiO ₂₎ of 0.9 g, was sealed and the resulting gel was charged to a Parr autoclave, at about 43rpm for 9 days Heated at 160 ° C. while rotating. The resulting fine powder-liquid mixture was filtered and the resulting solid was washed thoroughly with water and allowed to air dry overnight. The obtained solid was further dried in an oven at 120 ° C. for 3 hours to obtain 0.9 g of boron-ZSM-5 as shown by X-ray analysis.

Pt / B-ZSM-5 was prepared according to the following procedure. The boron-ZSM-5 sample synthesized according to the above example was baked to remove the template. Firing was performed as follows. A thin bed of material is heated from room temperature to 120 ° C. at a rate of 1 ° C. per minute in a muffle furnace and held at 120 ° C. for 1 hour. Next, the temperature is raised to 540 ° C. at the same rate, held at this temperature for 5 hours, then raised to 595 ° C. and held at that temperature for another 5 hours. The sample is blown with a 50/50 mixture of air and nitrogen at a rate of 20 standard cubic feet per minute during heating. By heating ammonium nitrate presence in water weakly acidic molecular sieve 3 hours (1g NH 4 _NO 3 / _10g of weakly acidic molecular sieve in water 1g of) the were calcined samples were ammonium nitrate and ion-exchange. The sample is then suspended in water (9 g of water per gram of weakly acidic molecular sieve) and Pt (NH ₃ ) ₄ (NO ₃ ) ₂ at a concentration that gives 0.5 wt% Pt with respect to the dry weight of the weakly acidic molecular sieve. A solution of was added. The pH of the solution was adjusted to 9 or less by gradually adding 0.15N ammonium hydroxide and stirred at 100 ° C. for 48 hours. After cooling, the mixture was filtered through a glass frit, washed with deionized water and dried at 120 ° C. The sample was then gradually fired in air to 300 ° C. and held at that temperature for 3 hours. The completed catalyst had a boron content of 0.18% by weight.

The catalyst was tested using n-C ₁₆ as described in Example 1 and the results are shown in Table 4. Using the value of 570 ° F. (conversion 57.9 percent) and the value of 580 ° F. (conversion 88%), the results in the final column for 80% conversion were linearly interpolated. Since C ₆ iso / normal ratio in both cases was zero, the absolute value of the percentage difference between these results is 0, the linear interpolation of the results, were appropriate.

  The data in Table 4 shows that high conversion operations are undesirable features: higher catalyst temperature, higher product iso / normal ratio, higher light product yield, and more valuable weight. It also shows that it tends to have the characteristic of lower product yields. This trend becomes more pronounced when the conversion rate exceeds 99%. Therefore, there is a motivation to operate at low conversion (25-50%) and recycle unconverted normal paraffin. However, the scale of the treatment equipment and catalyst packing becomes large when operated at low conversion, and the economic optimum is 25 to 99% conversion, most preferably 50 to 80% conversion, very preferably Is expected for conversions of 60 and 75%.

Compared to other hydroconversion catalysts, as shown in Table 6, Pt / B-ZSM-5 has several desirable characteristics when compared at 80% conversion: C ₆ iso / normal ratio. There (0 to 80% conversion) the lowest, C ₁₃ iso / normal ratio is the lowest (80% conversion 0), the lowest methane yield and activity has the feature that the highest. Therefore, it is the most preferred catalyst.

Example 3-Preparation and Testing of Pt / B-SSZ-64 SSZ-64 is an unknown structure that is believed to be a multidimensional zeolite with pores consisting of 10 and / or 12 ring structures. Boron-SSZ-64 was prepared by hydrothermal synthesis according to the following procedure. 4.8 g N-cyclobutylmethyl-N-ethylhexamethyleneiminium 0.62 M aqueous solution (3 mmol SDA), 1.0 g NaOH 1 M aqueous solution (1 mmol) on 23 cc Teflon liner NaOH) and 6.2 g of deionized water. To this mixture, 0.06 g sodium borate decahydrate (0.157 mmol Na ₂ B ₄ O ₇ · 10H ₂ O; 0.315 mmol or less B ₂ O ₃ ) was added and dissolved completely Stir until Then 0.9 g of CAB-O-SIL M5® (fused silica) is added to the solution, the mixture is stirred well, the resulting gel is sealed and charged to a Parr autoclave at 43 rpm for 12 days. And heated in an oven at 160 ° C. while rotating. The reaction mixture was filtered through a fritted glass funnel and the collected solid was washed thoroughly with water and then rinsed with acetone (20 ml or less) to remove any organic residue. The solid was air dried overnight and further dried in an oven at 120 ° C. for 1 hour to give 0.85 g of B-SSZ-64.

Pt / B-SSZ-64 was prepared according to the above procedure (Example 2) for producing Pt / B-ZSM-5 after calcination of the sample and ion exchange with NH ₄ NO ₃ . The pore volume of calcined SSZ-64 is 0.19 cm ³ / g, and SEM analysis shows a sheet-like structure of 0.5 to 1.0 μm.

The catalyst was tested using n-C ₁₆ as described in Example 1. The result at a conversion rate around 80% was obtained and a linear interpolation value at 80% conversion rate was derived. They are reported in Table 6.

Example 4 Preparation and Testing of Pt / B-SSZ-58 SSZ-58 is a two-dimensional zeolite in which all pores are composed of a 10-ring structure. Hydrothermal synthesis using the same procedure as described for Boron-SSZ-64 (Example 3) except that 1-cyclooctyl-1-butylpyrrolidinium hydroxide is used as a templating agent Boron-SSZ-58 was prepared with

Pt / B-SSZ-58 was prepared according to the procedure described in Example 2 for making Pt / B-ZSM-5. The pore volume of calcined SSZ-58 is 0.11 cm ³ / g, and SEM analysis shows cylinders and rod shapes of 2.5 μm or less. The Si / B molar ratio of the product was 42.

The catalyst was tested using n-C ₁₆ as described in Example 1 and results at conversions near 80% were obtained, leading to a linear interpolation at 80% conversion. They are reported in Table 6. This material showed the highest yield of the most valuable paraffin (C ₇ -C ₁₃ range).

Example 5-Preparation and Testing of Pt / B-SSZ-57 SSZ-57 is a zeolite of unknown structure, but is multidimensional and appears to consist of 10 and / or 12 ring structures. Boron-SSZ-57 was prepared according to the procedure described in Example 3 for making boron-SSZ-64 using 1-cyclohexyl-1-butylpyrrolidinium hydroxide.

Pt / B-SSZ-57 was prepared according to the procedure described in Example 2. The pore volume of calcined SSZ-57 is 0.13 cm ³ / g, and SEM analysis shows a cubic structure of 0.3 to 0.5 μm.

The catalyst was tested using n-C ₁₆ as described in Example 1 and results at conversions near 80% were obtained, leading to a linear interpolation at 80% conversion. They are reported in Table 6.

Example 6 Preparation and Testing of Pd / SSZ-46 (Ti-ZSM-11) SSZ-46 is a titanium-containing three-dimensional zeolite having a ZSM-11 structure with all pores having a 10-ring structure.

  A sample of this material was prepared according to Example 4 of US Patent No. 5,968,474 issued October 19, 1999 to Nakagawa et al.

The catalyst was tested using n-C ₁₆ as described in Example 1. Only one temperature was obtained which was close to 80% conversion but not exactly this value. However, this material shows the production of a product rich in normal paraffins.

  Compared to the results of Example 9 with Pt / B-ZSM-11 and Example 2 with Pt / B-ZSM-5, the Pd / SSZ-46 sample produced a higher amount of isomerized lighter paraffin product. It is extremely low activity. Therefore, boron is preferred over titanium, both of which are preferred over aluminum which introduces undesirable strong acidity.

Example 7-Preparation and Testing of Pt / B-SSZ-53 SSZ-53 is a one-dimensional zeolite having pores consisting of a 14-ring structure. Borosilicate SSZ-53 was synthesized according to the procedure described in Example 3 using trimethyl- (1-phenyl-cyclohexylmethyl) -ammonium hydroxide as a templating agent.

Pt / B-SSZ-53 was prepared according to the procedure detailed in Example 2. The pore volume of calcined SSZ-53 is 0.13 cm ³ / g, and SEM analysis shows a lath-like structure of 0.5 to 1.0 μm. The Si / B molar ratio of the product was 39.

The catalyst was tested using n-C ₁₆ as described in Example 1 and results at conversions near 80% were obtained, leading to a linear interpolation at 80% conversion. They are reported in Table 6.

Example 8-Preparation and testing of Pd / B-SSZ-58 A sample of B-SSZ-58 was prepared by the same procedure used in Example 5.

The purpose of this experiment was to measure the effect of metal selection. As described in Example 4 for preparing Pt / B-SSZ-58 by using Pd (NH ₃ ) ₄ (NO ₃ ) ₂ solution instead of Pt (NH ₃ ) ₄ (NO ₃ ) ₂ solution. Palladium / boron-SSZ-58 was prepared according to the procedure described.

The catalyst was tested using n-C ₁₆ as described in Example 1 and results at conversions near 80% were obtained, leading to a linear interpolation at 80% conversion. They are reported in Table 6. These results indicate that using Pd as the metal can give good sensitivity to normal products, but it is not as effective as Pt. This catalyst did not exhibit the highly desirable characteristics that the catalyst minimizes the undesired propane and butane yields.

Example 9 Preparation and Testing of Pt / B-ZSM-11 Borosilicate according to the zeolite synthesis procedure described in Example 2 for making ZSM-5 using tetrabutylammonium hydroxide as a templating agent ZSM-11 was synthesized.

  Pt / B-ZSM-11 was prepared according to Example 2.

The catalyst was tested using n-C ₁₆ as described in Example 1 and results at conversions near 80% were obtained, leading to a linear interpolation at 80% conversion. They are reported in Table 6.

Example 10-Preparation and Testing of Pt / B-SSZ-59 SSZ-59 is a one-dimensional zeolite whose pores have a 14-ring structure. Borosilicate SSZ-59 was synthesized according to the procedure described in Example 3 using 1-methyl-1- (1-phenyl-cyclopentylmethyl) -piperidinium hydroxide as a templating agent.

Pt / B-SSZ-59 was prepared according to Example 2. The pore volume of calcined SSZ-59 is 0.14 cm ³ / g, and SEM analysis shows a 0.5 μ long needle-like structure.

The catalyst was tested using n-C ₁₆ as described in Example 1 and results at conversions near 80% were obtained, leading to a linear interpolation at 80% conversion. They are reported in Table 6.

Example 11-Preparation and Testing of Pt / B-SSZ-55 SSZ-55 is a one-dimensional zeolite whose pores have a 12-ring structure. Borosilicate SSZ-55 was synthesized according to the weakly acidic molecular sieve synthesis procedure described in Example 3 using [1- (3-fluoro-phenyl) -cyclopentylmethyl] -trimethyl-ammonium hydroxide as a templating agent. .

Pt / B-SSZ-55 was produced according to Example 2. The pore volume of calcined SSZ-55 is 0.15 cm ³ / g, and SEM analysis shows a 2 to 5 μ rice grain structure.

The catalyst was tested using n-C ₁₆ as described in Example 1 and results at conversions near 80% were obtained, leading to a linear interpolation at 80% conversion. They are reported in Table 6.

Comparative Example 12 Preparation and Testing of Pd / HY This is a comparative example of a commercially available noble metal hydrocracking catalyst and is not the subject of the present invention. The material was prepared according to Bezman U.S. Pat. No. 5,141,909 issued Aug. 25, 1992, except that the catalyst was not contacted with nitrogen. The aluminum in the Y zeolite of this sample, which is necessary for conventional hydrocracking, imparts an undesirably strong acidity in normal paraffin hydroconversion.

The catalyst was tested using n-C ₁₆ as described in Example 1 and results at conversions near 80% were obtained, leading to a linear interpolation at 80% conversion. They are reported in Table 6. This demonstrates that conventional hydrocracking catalysts of this type usually provide isomerized light paraffins and do not provide the normal paraffins desirable in the present invention.

Comparative Example 13-Preparation and Testing of Sulfurized NiW / Silica Alumina This is a comparative example of a commercially available base metal hydrocracking catalyst and not the subject of the present invention. Although not containing zeolite, aluminum in amorphous silica alumina, which is necessary for conventional hydrocracking, imparts undesirably strong acidity in normal paraffin hydroconversion.

The catalyst was tested using n-C ₁₆ as described in Example 1 and results at conversions near 80% were obtained, leading to a linear interpolation at 80% conversion. They are reported in Table 6. This demonstrates that conventional hydrocracking catalysts of this type usually give isomerized light paraffins and high methane yields and do not give the normal paraffins desirable in the present invention. A high methane yield indicates undesirable hydrogenolysis.

Example 14-Preparation and Testing of Pt / B-SSZ-33 SSZ-33 is a multidimensional zeolite whose pores consist of 12 and 10 ring structures. B-SSZ-33 was synthesized as follows. 2.0 moles of trimethylammonium-8-tricyclo [5.2.1.0] decane in 3700 ml water is mixed with 3600 ml water, 92 grams boric acid and 39 grams solid NaOH. Once a clear solution is obtained, add 558 grams of Cabosil M-5 and add 5 grams of ready-made B-SSZ-33 seed material. The entire contents are mixed in a Hastelloy liner used in 5 gallon autoclaves (Autoclave Engineers). Stir the reaction at 200 rpm overnight at room temperature. The reactor is then warmed to 160 ° C. over 12 hours and the stirring speed is reduced to 75 rpm. The reaction is kept under these conditions for a processing time of 10 days. The recovered precipitated product is crystalline B-SSZ-33 according to US Pat. No. 4,963,337 issued Oct. 16, 1990 to Zones. The water used in this example should be distilled or deionized water to ensure that no aluminum is introduced. Other reactants and components should also be selected so that essentially no aluminum is present.

A calcined sample by adding aqueous ammonium nitrate (0.1506 g Pt (NH ₃ ) ₄ (NO ₃ ) ₂ ) in 35.3 g deionized water to 15.15 g B-SSZ-33 by dry weight at 350 ° C. Impregnated. After 48 hours at room temperature, the mixture was dried in a 110 ° C. vacuum oven for 3 hours. The sample was then fired in air as follows. Heat from room temperature to 120 ° C in 1 hour, maintain at 120 ° C for 1 hour, heat from 120 ° C to 300 ° C in 3 hours, maintain at 300 ° C for 5 hours, then cool to room temperature, to dry zeolite To obtain a calcined Pt / B-SSZ-33 catalyst containing 0.5% by weight of Pt. Pt / B-SSZ-33 was then pelletized to 24-42 mesh for use in catalytic testing.

The catalyst was tested using n-C ₁₆ as described in Example 1 and results at conversions near 80% were obtained, leading to a linear interpolation at 80% conversion. They are reported in Table 6.

Example 15-Influence of raw material sulfur The Pt-B-ZSM-5 catalyst of Example 5 was sulfided at atmospheric pressure under the following conditions.
(1) First, 0.5 gram of catalyst was purged with 100 cc / min N ₂ at room temperature for 10 minutes. It was then heated to 400 ° F. in 30 minutes at the same flow rate of N ₂ and held at 400 ° F. for 30 minutes in a N ₂ flow.
(2) To reduce the catalyst, the catalyst was treated with a H ₂ flow (100 cc / min) at 400 ° F. for 10 hours, then heated to 900 ° F. in the same H ₂ flow for 1 hour, and H ₂ (100 cc At 900 ° F. for 2 hours.
(3) The catalyst was then cooled to 800 ° F. in 30 minutes in a H ₂ stream (100 cc / min).
(4) The catalyst was then sulfided for 1 hour at 800 ° F. in an H ₂ flow of 34 cc / min with an n-heptane feedstock containing 75 ppm sulfur (as difluidized dimethyl) at a feed rate of 38.4 cc / hour. did.
(5) The n-heptane feed was then stopped and the catalyst was heated from 800 to 900 ° F. in a 300 cc / min H ₂ flow and maintained at 900 ° F. for 30 minutes in the same H ₂ flow.
(6) Finally, the catalyst was cooled to room temperature in 2 hours in a H ₂ flow of 100 cc / min.
(7) The catalyst was then ready for another catalytic test reaction.

This amount of sulfur corresponds to an S / Pt stoichiometry of 4.75 and is sufficient to produce detectable H ₂ S in the effluent gas.

The sulfided catalyst was tested using n-C ₁₆ as described in Example 1 and results at conversions near 80% were obtained to derive a linear interpolation at 80% conversion. They are reported in Table 7 along with the results for the non-sulfurized catalyst according to Example 2.

  These results show that exposure of the catalyst to sulfur reduces the activity to some extent and slightly increases the iso / normal ratio of the product, but advantageously increases the production of higher value heavy normal paraffins. Show. This yield change reduces valuable hydrogen consumption by about 100 SCF / B. Therefore, the sulfur content of the feed should be less than 100 ppm, for example 0.1 to 10 ppm. The sulfur content can be adjusted by hydrotreating a high sulfur feedstock or by increasing the sulfur content of a low sulfur feedstock (such as a Fischer-Tropsch derived feedstock). Continuously mixed with high-sulfur feedstock (petroleum feedstock, etc.) or by pre-sulfiding the catalyst, or sulfur-containing components (disulfurized dimethyl, mercaptan, hydrogen sulfide, sweetened extract, etc.) continuously By adding, the sulfur content of the low sulfur raw material can be increased. If sulfur is required to improve selectivity, sulfur can be added continuously or intermittently.

Example 16-Effect of feed nitrogen The Pt-B-ZSM-5 catalyst of Example 15 was further tested using an n-C ₁₆ feed containing 5 ppm by weight of nitrogen as butylamine. Under the reaction conditions, butylamine decomposes to give ammonia and butene. Ammonia serves to titrate strong Bronsted acid positions. Using this feedstock, the catalyst was tested at temperatures from 550 ° F to 670 ° F by increasing the temperature in 10 ° F increments as described in Example 1. Overall n-C ₁₆ conversion increased from 9.9% to 99.7% over this temperature range. The result at a conversion rate around 80% was obtained and a linear interpolation value at 80% conversion rate was derived. They are reported in Table 7 along with the results for the non-sulfurized catalyst according to Example 2.

  These results indicate that non-acidic borosilicate has significant resistance to nitrogen. Activity is improved upon contact with nitrogen. Without wishing to be bound by any theory, this is seen between Experiment 15 for the sulfurized catalyst and Experiment 2 for the catalyst prior to the elimination of the sulfur from the catalyst and contact with any heteroatoms. It is thought to be due to a slight reversal of the changes made. Nitrogen is thought to have little or no effect on the catalyst.

Example 17 Effect of Boron Content in B-ZSM-5 A series of Pt-B-ZSM-5 catalysts without aluminum and with varying amounts of boron were prepared.

Comparative Example 17a. Synthesis of All-Silica ZSM-5 (Sample 53353) A sample of this all-silica-ZSM-5 was made hot water according to the following procedure. In a 23 cc Teflon liner, 2.5 g of 25% by weight aqueous solution of tetrapropylammonium hydroxide, 1.25 g of 1N NaOH, 8 g of deionized water and 1 g of CAB-O-SIL M-5 (molten) silica -98% SiO ₂₎ were mixed thoroughly. The resulting gel was sealed and charged in a Parr autoclave and heated at 160 ° C. with rotation at about 43 rpm for 12 days. The resulting fine powder-liquid mixture was filtered and the resulting solid was washed thoroughly with water and allowed to air dry overnight. The obtained solid was further dried in an oven at 120 ° C. for 3 hours to obtain 0.88 g of total silica-ZSM-5 (X-ray analysis).

Pt / total silica-ZSM was prepared according to the following procedure. The all-silica-ZSM-5 sample synthesized according to the above example was baked to remove the template. Firing was performed as follows. A thin bed of material is heated from room temperature to 120 ° C. at a rate of 1 ° C. per minute in a muffle furnace and held at 120 ° C. for 1 hour. Next, the temperature is raised to 540 ° C. at the same rate, held at this temperature for 5 hours, then raised to 595 ° C. and held at that temperature for another 5 hours. The sample is blown with a 50/50 mixture of air and nitrogen at a rate of 20 standard cubic feet per minute during heating. By heating for 3 hours in the presence in water zeolite _(NH 4 _NO 3 / 10g of zeolite in water 1g of 1g) of ammonium nitrate, and calcined samples were ammonium nitrate and ion-exchange. The sample was then suspended in water (9 g water per gram of zeolite) and a Pt (NH ₃ ) ₄ (NO ₃ ) ₂ solution at a concentration giving 0.5 wt% Pt relative to the dry weight of the zeolite was added. . The pH of the solution was adjusted to 9 or less by gradually adding 0.15N ammonium hydroxide and stirred at 100 ° C. for 48 hours. After cooling, the mixture was filtered through a glass frit, washed with deionized water and dried at 120 ° C. The sample was then gradually fired in air to 300 ° C. and held at that temperature for 3 hours.

  When the platinum content of this sample was investigated, it was found that it was hardly mixed. In contrast, samples with boron, less than 0.10 wt.% Aluminum, or combinations thereof contained the expected amount.

17b. Synthesis of B-ZSM-5 This sample was synthesized according to the synthesis procedure described above for the synthesis of all silica samples, except that 0.01 g Na ₂ B ₄ O ₇ (anhydrous) was added. A Pt version was synthesized according to the above procedure. Platinum was observed in this sample, but less than expected. This indicates that the silanol groups in all silica samples are strong enough to act as an effective exchange site with the metal.

An analysis of these zeolites and their catalytic performance is shown in Table 8.

  The all silica sample (17a) was inert and the conversion was only 10.8% at 750 ° F. Results at 80% conversion could not be determined experimentally and it was estimated that a temperature above 970 ° F. was required. It does not contain a sufficient amount of boron for use. The sample with 0.1 wt% boron was more active, but less active than the sample with 0.18 wt% boron. These results show that for the ZSM-5 structure, the boron content exceeds about 0.05 wt% (equivalent to or better than a catalyst temperature of 800 ° F.), for example about 0.125 wt% (700 ° It has been demonstrated that it should be above or equal to or better than the catalyst temperature of F, or about 0.15% by weight (equal to or better than the catalyst temperature of 600 ° F.). These relationships between boron content and catalytic activity are for ZSM-5. They are likely to depend on the structure of the weakly acidic molecular sieve.

Example 18-Effect of aluminum content in B-ZSM-5 A series of Pt-B-ZSM-5 catalysts were prepared with varying amounts of aluminum.

18a. Synthesis of Aluminum-Containing B-ZSM-5 A sample of this trace amount of aluminum-containing boron-ZSM-5 was produced in hot water according to the following procedure. In a 23 cc Teflon liner, 0.8 g of 40% by weight aqueous solution of tetrapropylammonium hydroxide, 1.25 g of 1N NaOH, 10 g of deionized water and 0.0033 g of sodium borate were added by sodium borate. Mix thoroughly until completely dissolved. Then, 0.9 g of CAB-O-SIL M-5 ( fused silica -98% SiO ₂₎ and 0.001 g Na-Y zeolite _{(SiO 2 / Al 2 O 3} = 5: Solid 115ppm or less, or the total gel mixture 0.000112 g of Al) corresponding to 10 ppm or less was added and the mixture was mixed well. The resulting gel was sealed and charged in a Parr autoclave and heated at 160 ° C. with rotation at about 43 rpm for 12 days. The resulting fine powder-liquid mixture was filtered and the resulting solid was rinsed thoroughly with water and allowed to air dry overnight. The dried product was then suspended in 5 ml of 0.01 N HCl and heated at 80 ° C. (static) to ensure that any unreacted Na—Y was completely destroyed. The solid was filtered, dried in open air, and further dried in an oven at 120 ° C. for 3 hours to give 0.83 g of ZSM-5 (X-ray analysis).

  The calculated aluminum content of this material was 145 ppm and the measured boron content was 0.21% by weight.

This sample, Pt / ZSM-5, was prepared according to the following procedure. The sample synthesized according to the above example was baked to remove the mold. Firing was performed as follows. A thin bed of material is heated from room temperature to 120 ° C. at a rate of 1 ° C. per minute in a muffle furnace and held at 120 ° C. for 1 hour. Next, the temperature is raised to 540 ° C. at the same rate, held at this temperature for 5 hours, then raised to 595 ° C. and held at that temperature for another 5 hours. The sample is blown with a 50/50 mixture of air and nitrogen at a rate of 20 standard cubic feet per minute during heating. By heating for 3 hours in the presence in water zeolite _(NH 4 _NO 3 / 10g of zeolite in water 1g of 1g) of ammonium nitrate, and calcined samples were ammonium nitrate and ion-exchange. This sample in the form of NH _{4 is} then suspended in water (9 g of water per gram of zeolite) and Pt (NH ₃ ) ₄ (NO ₃ ) at a concentration giving 0.5 wt% Pt relative to the dry weight of the zeolite. _Two solutions were added. The pH of the solution was adjusted to 9.2 or lower by gradually adding 0.15N ammonium hydroxide and stirred at 95 ° C. for 48 hours. After cooling, the mixture was filtered through a glass frit, washed with deionized water and dried at 120 ° C. The sample was then gradually fired in air to 300 ° C. and held at that temperature for 3 hours. The sample was then pelleted with Carver Press, converted to 24-40 mesh and used as a catalyst.

18b. Synthesis of Aluminum-Containing B-ZSM-5 A sample of this aluminum-containing boron-ZSM-5 was hydrothermally produced according to the following procedure. In a 23 cc Teflon liner, 2.45 g of 25% by weight aqueous solution of tetrapropylammonium hydroxide, 1.2 g of 1N NaOH, 8.35 g of deionized water and 0.06 g of sodium borate decahydrate The product was mixed well until the sodium borate was completely dissolved. Then 0.9 g CAB-O-SIL M-5 (fused silica-98% SiO ₂ ) and 0.0025 g Na-A zeolite (SiO ₂ / Al ₂ O ₃ = 1.7; corresponding to 385 ppm or less 00003 g Al) was added and the mixture was mixed well. The resulting gel was sealed and charged in a Parr autoclave and heated at 160 ° C. with rotation at about 43 rpm for 12 days. The resulting fine powder-liquid mixture was filtered and the resulting solid was rinsed thoroughly with water and allowed to air dry overnight. The dried product was then suspended in 5 ml of 0.01 N HCl and heated at 80 ° C. (static) to ensure that any unreacted Na—Y was completely destroyed. The solid was filtered, dried with open air and further dried in an oven at 120 ° C. for 3 hours to give 0.8 g of ZSM-5 (X-ray analysis).

  The calcined aluminum content of this material was 402 ppm and the measured boron content was 0.21% by weight.

  This sample, Pt / Al-B-ZSM-5, was prepared according to the procedure used for sample 18a.

18c. Synthesis of aluminum-containing B-ZSM-5 This sample was synthesized according to the procedure for sample 18b except that 0.005 g of NA zeolite (Al 0.00074 g) was used.

  The calcined aluminum content of this material was 785 ppm and the measured boron content was 0.22% by weight.

  This sample, Pt / Al-B-ZSM-5, was prepared according to the procedure used for sample 18a.

18d. Synthesis of aluminum-containing B-ZSM-5 This sample was synthesized according to the above procedure except that 0.007 g of NA zeolite (Al 0.001 g) was used.

  The calculated aluminum content of this material was 1000 ppm and the measured boron content was 0.18% by weight.

  This sample, Pt / Al-B-ZSM-5, was prepared according to the procedure used for sample 18a.

18e. Synthesis of aluminum-containing B-ZSM-5 This sample was synthesized according to the above procedure except that 0.01 g NA zeolite (Al 0.00148 g) was used.

  The calcined aluminum content of this material was 1500 ppm and the measured boron content was 0.17% by weight.

  This sample, Pt / Al-B-ZSM-5, was prepared according to the procedure used for sample 18a.

An analysis of these zeolites and their catalytic performance is shown in Table 9.

  These results demonstrate that for the production of lighter products with low iso / normal paraffin ratio from n-paraffins, the molecular sieve aluminum content should be less than 1000 ppm, for example less than 200 ppm or less than 20 ppm. is doing. Since the molecular sieve structure can also affect the product iso / normal ratio, the exact aluminum content required for a given structure to obtain the desired product iso / normal ratio is less than these values. Also good.

Example 19-Test with Fischer-Tropsch wax A 10 gram sample of Pt / B-SSZ-58 was prepared according to the procedure of Example 4. It was tested in a trickle bed microunit operating in a downflow mode. The catalyst was converted to pellets and 7.0 cc was charged to the reactor. It was reduced with hydrogen at 450 ° F. The reactor inlet pressure was adjusted to match the target (initially 1000 psig) and the gas flow rate was adjusted to 10000 SCFB. Next, the supply was started at 1.0 LHSV. The catalyst temperature was adjusted to give a series of feed conversions.

  The microunit configuration made it possible to calculate product yield, feed conversion and mass balance based on detailed feed and product analysis (ASTM D-2887 simulated distillation, gas analysis).

  The feed was Fischer-Tropsch wax prepared by a slurry bed process using a cobalt catalyst. The wax was hydrotreated to remove impurities (olefins, nitrogen, oxides, solids, etc.). Properties of the hydrotreated wax are shown in Tables 10 and 11.

The catalyst was evaluated at various pressures and temperatures and the yield is shown in Table 12. Lowering the pressure increased the activity of the catalyst.

GC analysis of the added portion of the total liquid product by unit showed a large peak due to normal paraffin with a very small intermediate peak. A portion of the product from 666 hours was distilled by D-1160 at the 650 ° F. cut to produce a bottom product, an overhead product, and a light material present in the trap. The product was analyzed for density, normal paraffin content and distribution, cetane index as shown in Table 13.

  The distillation product is rich in normal paraffins, and the overhead fraction has a high cetane index that indicates its good potential as a diesel fuel.

The wax feed was converted to a lighter product while maintaining a high normal paraffin structure. Selectivity for normal paraffin conversion is defined as the ratio of produced n-C ₂₂ and lighter paraffin to n-C ₂₃ and heavier normal paraffin in the feed. n-C ₂₂ was chosen as a reference because it corresponds to a boiling point of about 700 ° F.

  In this product, the n-paraffin selectivity is approximately 98.4%, and the yield of the product based on the raw material is taken as the yield from D1160 distillation. The amount of light gas produced is small.

  The total liquid product from 666 hours was solvent dewaxed by the following procedure.

Laboratory solvent dewaxing procedure The wax sample was heated to just above its pour point. 100 grams was poured into a tared 1 liter glass beaker on a balance and weighed to the second decimal place. 200 mL of toluene was added followed by 200 mol of methyl ethyl ketone. Gently stirred until the sample was dissolved. When completely dissolved, the sample in the beaker was covered with a piece of aluminum foil, charged into a refrigerator set in advance at the desired temperature (−10 ° F.), and allowed to stand overnight.

  Filtration was performed in one room of a refrigerator equipped with a vacuum line and toggle switch. The filtration assembly consisted of a Buchner 186 mm funnel at the top of a 2 liter filtration flask. All equipment including the filtration assembly spatula, additional ketones, etc. were housed in a refrigerator so that they were in thermal equilibrium.

  Whatman filter paper no. 4 (diameter 18.5 cm) was placed in a Buchner funnel. A powerful vacuum hose was attached to the vacuum line in the refrigerator.

Filtration procedure The filter paper was pre-wetted with 20 ml cold ketone.
2. The toggle switch to vacuum was opened.
3. The sample in the beaker was stirred with a spatula and quantitatively transferred to the funnel. The side of the beaker was rubbed to remove excess sample.
4). The side of the beaker was rinsed with 200 ml of cold ketone.
5. The refrigerator was closed and the mixture was filtered.
6). The cracks in the filter cake were smoothed with a spatula to smooth the surface.
7. 200 ml of cold ketone was poured into the sample to rinse the residual oil.
8). Steps 6 and 7 were repeated.

Wax recovery procedure The filter cake was dried and the vacuum was broken. The wax was transferred to a pre-tared bottle. 100 mL boiling toluene was poured onto the edge of the filter paper to dissolve any remaining wax. Toluene was collected in a bottle. To evaporate the solvent, the bottle was placed on a hot plate under low heat and contacted with a gentle stream of nitrogen. After the solvent is removed, the recovered wax is weighed.

Oil recovery procedure The filtrate was poured into a pre-tared 1 liter round bottom flask and then stripped using a rotary evaporator equipped with a stream of nitrogen. The oil-solvent mixture was heated to 120 ° in an oil bath and stripped for a minimum of 4 hours. The amount of oil recovered was then measured.

Due to the large amount of light material, the amount of recovered wax and dewaxed oil was small. Properties of dewaxed oil and wax are shown in Table 14.

Comparative Example 20-Test on Fischer-Tropsch Wax without Added Hydrogen According to Example 15, the Pt / B-SSZ-58 catalyst was left in the microunit at a temperature above 250 psig and 725 ° F, but replaced with nitrogen gas It was used. The catalytic activity for normal paraffin conversion disappeared immediately and no significant conversion occurred even at elevated temperatures.

  After 29 hours at 250 psig, above 725 ° F. and in the absence of hydrogen, hydrogen was reintroduced and the nitrogen gas flow was stopped. The catalytic activity recovered rapidly to the initial value measured by the appearance of the product GC trace. This demonstrates the remarkable resistance of the catalyst to hydrogen interruption. This is an advantage compared to conventional hydrogen conversion catalysts.

Example 21-Testing on n-paraffin containing petroleum feed According to Example 20, a wax hydrocracked Chinese feed was treated with a Pt / B-SSZ-58 catalyst. The catalyst was very stable at moderate conversion levels and low pressure (less than 300 psig), giving good yields of distillate fuel. The conversion rate improved as the pressure decreased. Table 10 shows the characteristics of the raw materials. The yields under various processing conditions are shown in Table 15, and the analytical values of the products by D-1160 distillation of the products at 1362 and 1434 hours are shown in Table 16.

These results indicate that a high cetane index product is produced with a bottom product that is deficient in normal paraffin. The bottom product was solvent dewaxed to give a dewaxed oil having the properties shown in Table 17. The n-paraffin selectivity for this feed is about 61%. Clearly, in raw materials containing moderate amounts of n-paraffins, some of the n-paraffins are hydroconverted to form other products, possibly isoparaffins, cycloparaffins or alkyl groups. Thus, if an n-paraffin product is desired, the feed must contain more than 5% by weight n-paraffins, preferably more than 50% by weight n-paraffins, more preferably more than 80% by weight n-paraffins. I must.

  These results show that a high viscosity index product can be produced by a combination of n-paraffin selective hydroconversion and solvent dewaxing.

Example 22 Preparation of Large Scale Sample of Pt / B-SSZ-33 Borosilicate SSZ-33 was synthesized according to the procedure of Example 14 as follows.

Pt / B-SSZ-33 was produced according to the following procedure. The B-SSZ-33 sample was baked to remove the mold. Firing was performed as follows. A thin bed of material is heated from room temperature to 120 ° C. at a rate of 1 ° C. per minute in a muffle furnace and held at 120 ° C. for 1 hour. Next, the temperature is raised to 540 ° C. at the same rate, and kept at this temperature for 5 hours. The atmosphere for firing is nitrogen at a flow rate of 20 standard cubic feet / minute, with a small amount of air being pumped into the fluid. The pore volume of calcined B-SSZ-33 was 0.21 cm ³ / g. The Si / B molar ratio of the product was 18.

The calcined sample was impregnated by adding an aqueous ammonium nitrate solution (0.1506 g of Pt (NH ₃ ) ₄ (NO ₃ ) ₂ ) in 35.3 g of deionized water to 15.15 g of zeolite at dry weight at 350 ° C. After 48 hours at room temperature, the mixture was dried in a vacuum oven at 110 ° C. for 3 hours. The sample was then fired in air as follows. Heat from room temperature to 120 ° C in 1 hour, maintain at 120 ° C for 1 hour, heat from 120 ° C to 300 ° C in 3 hours, maintain at 300 ° C for 5 hours, then cool to room temperature, to dry zeolite To obtain calcined Pt / B-SSZ-33 containing 0.5% by weight of Pt. Pt / B-SSZ-33 was then pelletized to 24-42 mesh for use in catalytic testing.

Example 23-Catalyst Test of Pt / B-SSZ-33 Using the Dartin raw material described in Example 19, the catalyst of Example 22 was tested in micro units. The results are shown in Table 18.

The catalyst has proven to be significantly stable when processed at high conversion and low pressure. The yield of C ₄ -gas was as low as the yield of naphtha product. The catalyst was most selective for the distillation product.

Overhead product recovered from on-line distillation from 570 to 618 hours was distilled by D-1160 into a crude fraction simulating naphtha, jet and diesel. Their products are shown in Table 19. The jet fraction has an excellent smoke point.

  Although the product contained a significant amount of n-paraffins, the SSZ-33 catalyst contains a 12-ring structure, so not only n-paraffins in the feed, but also non-n-paraffins (isoparaffins and cyclic compounds). Was also converted.

The bottom product from online distillation was solvent dewaxed and the product was analyzed as shown in Table 20.

  The dewaxed oil provided a high VI lubricant. The VI of the product after treatment for 450 hours was 114.

The original strip liquid product (SLP), dewaxed oil (DWO) and wax were further analyzed for the normal paraffin content shown in Table 21.

Example 24-Preparation and Testing of Pt / B-SSZ-60 SSZ-60 is a one-dimensional 10-ring zeolite. B-SSZ-60 is an Elomari U.S. Patent No. 6,620,401 issued on September 16, 2003 (Examples 3 and 4) and an Elomari U.S. Patent issued on April 1, 2003. No. 6,540,906. Example 8 of US Pat. No. 6,620,401 describes a test of Pt / Al-SSZ-60 prepared by converting B-SSZ-60 to aluminosilicate zeolite. The results show that aluminum incorporation produces undesirable acidity as indicated by the high product iso / normal ratio.

Pt / B-SSZ-60 was prepared by the same method used in Example 2. The catalyst was tested using n-C ₁₆ as described in Example 1. The result at a conversion rate around 80% was obtained and a linear interpolation value at 80% conversion rate was derived. The results are shown in Table 22.

Example 25-Preparation and Testing of Pt / B-SSZ-70 SSZ-70 is believed to be a four-dimensional 10-ring zeolite. It has two sets of two-dimensional 10-ring pores. B-SSZ-70 was prepared by mixing 18: 1 Si / B molar ratio tetraethylorthosilicate and triethylboric acid with a 1 molar solution of diisopropylimidazolium to obtain a Si / template molar ratio of 2; The ethanol was then removed by evaporation in a hood for several days. The contents of the tared reactor (Parr 4745 stainless steel reactor Teflon® cup) were then adjusted with water to achieve a H ₂ O / Si molar ratio of 18. Finally, 50% HF was converted drop by drop while stirring the contents using a plastic spatula to give a Si / F molar ratio of 2. The reaction was then heated to 150 ° C. for 80 days.

Pt / B-SSZ-70 was prepared by the same method used in Example 2. The catalyst was tested using n-C ₁₆ as described in Example 1. The result at a conversion rate around 80% was obtained and a linear interpolation value at 80% conversion rate was derived. The results are shown in Table 22.

  These results show that other 10-ring zeolites can give products with very low iso / normal ratios, but B-ZSM-5 materials are preferred due to their high activity.

Example 26-Preparation and Testing of Pt / B-SSZ-13 Two samples of boron-SSZ-13 were prepared and converted to Pt catalyst. SSZ-13 is an octacyclic zeolite with an orthopyroxene structure. The aluminum content of boric acid used in both preparations was measured to be less than 5 ppm. The composition of Cab-O-Sil M-5 was 3 ppm aluminum and 7 ppm sodium.

Example 26A: This boron-SSZ-13 sample was hydrothermally produced according to the following procedure. In a 600 cc Teflon liner, 134.61 g 0.72 molar N, N, N-trimethyl-1-adamantyl ammonium hydroxide and 41.15 g 0.28 molar N, N, N-trimethyl hydroxide 2.15 g of boric acid is dissolved in a mixture consisting of 1-adamantyl ammonium. Cab-O-Sil M-5 boron SSZ-13 seeds and 26.13g of 0.72g of (fused silica -98% SiO ₂₎ is added with stirring. After thorough mixing, the gel obtained was charged into a 600 cc stirred autoclave and heated at 160 ° C. and 75 rpm for 3 days. The resulting mixture was filtered, washed with deionized H ₂ O, and dried at 95 ° C. to give 31.53 g of boron SSZ-13 (X-ray analysis).

  The measured boron and aluminum content is 0.64% by weight boron and 15 ppm aluminum. The measured sodium content was 187 ppm.

Example 26B: This boron-SSZ-13 sample was hydrothermally produced according to the following procedure. In a 23 cc Teflon liner, 9.70 g 0.62 molar N, N, N-trimethyl-1-adamantyl ammonium hydroxide, 0.12 g sodium chloride, 0.12 g boric acid, 1.45 g was added Cab-O-Sil M-5 boron -SSZ-13 seeds (fused silica -98% SiO ₂₎ and 0.04 g, the mixture was then mixed thoroughly. The resulting gel was sealed and charged in a Parr autoclave and heated at 160 ° C. while rotating at about 43 rpm for 5 days. The resulting mixture was filtered and the resulting solid was thoroughly rinsed with water and air dried to give 1.64 g boron-SSZ-13 (X-ray analysis).

  The measured boron content was 0.63% by weight. Based on the aluminum content of the silicon and boron reagents, the calculated aluminum content should be less than 200 ppm, perhaps less than 10 ppm. The measured sodium content was 3569 ppm.

Preparation of Pt catalyst Platinum impregnation by incipient wetness was performed by first measuring the volume of water required to achieve incipient wetness in known amounts of zeolite. This was done by drying 1 gram of zeolite in a tared 60 cc pierced bottle at 300 ° C. for 3 hours and then sealing it at elevated temperatures. Upon cooling, the dry weight of the zeolite was measured by the weight difference. The pierced bottle containing the zeolite was then tared again and water was introduced with a syringe until initial wetting was achieved. The initial wet capacity required per gram of dry zeolite was calculated from the weight difference.

  For actual platinum impregnation, the other fraction of the zeolite was dried in a pierced bottle as described above and the volume of water required to pre-wet was calculated. Next, tetraamine platinum nitrate for filling with 5% Pt was dissolved in the volume of water, and the solution was injected into the pierce bottom with a syringe. The catalyst was left overnight and then the pierced bottle was opened. The catalyst was dried and then calcined in an oven with flowing air by raising the temperature to 288 ° C. at a rate of 1 ° C./hour and then held at this temperature for 3 hours.

The Pt catalyst was tested using n-C ₁₆ as described in Example 1. The result at a conversion rate around 80% was obtained and a linear interpolation value at 80% conversion rate was derived. The results are shown in Table 23. These demonstrate that 8-ring zeolites can also be used as catalysts in this process. Sample 26B exhibits lower activity and a higher product iso / normal ratio. This is probably due to the higher sodium content in this sample that reduces activity. Therefore, when sodium is added with the intention of reducing the activity at the strongly acidic position, an excessive amount should be avoided because it results in a decrease in activity. The higher temperature required to work a less active catalyst will result in a higher iso / normal ratio product.

Example 27-Preparation and test of Pt / B-MTT A zeolite with an MTT structure having one-dimensional 10-ring pores was prepared. The preparation consisted of two parts: seed preparation and subsequent catalyst preparation.

Seed Preparation In a 23 cc Teflon liner, 0.90 g of 1N KOH and 0.70 g of N-isopropyl-1,3-propanediamine were dissolved in 10.6 g of deionized water. Then 0.07 g potassium borate tetrahydrate was dissolved in the mixture, then 0.90 g Cabosil M-5 was added and mixed to produce a homogeneous suspension. Then 0.03 g of B-MTT seed from previous synthesis (Si / B = 49) was added to the mixture. The liner was then sealed and sealed in a 23 ml steel Parr autoclave and subsequently charged into a 160 ° C. oven with a rotating skewer (43 rpm). After 4 days, the resulting solid was filtered, washed with about 500 mL deionized water, and dried in an oven at 90 ° C. Powder X-ray diffraction showed that the sample was pure B-MTT. ICP showed a Si / B molar ratio of 34.

Preparation of B-MTT In a 23 cc Teflon liner, 0.90 g of 0.1 N KOH, 10.6 g of deionized water, and 0.70 g of N-isopropyl-1,3-propanediamine. Mixed. Next, 0.11 g of potassium borate tetrahydrate was dissolved in the solution. 0.90 g Cabosil M-5 was then added and mixed to produce a homogeneous suspension. 0.03 g B-MTT seed was added. The liner was then sealed and sealed in a 23 ml steel Parr autoclave and subsequently charged into a 160 ° C. oven with a rotating skewer (43 rpm). After 7 days, the autoclave was removed and cooled to room temperature. Then 1.0 g of additional KOH was added to the mixture, which was then resealed and heated for an additional 4 days. At that time, the resulting solid was filtered, washed with about 500 mL deionized water, and dried in an oven at 90 ° C. Powder X-ray diffraction showed that the sample was pure B-MTT.

Catalyst Preparation Pt-B-SSZ-13 described in Example 26, except that the Pt impregnated catalyst was calcined and the water pore volume was estimated from results obtained for other samples rather than measurements. Prepared according to the procedure.

Catalyst Testing Pt catalysts were tested using n-C ₁₆ as described in Example 1. The result at a conversion rate around 80% was obtained and a linear interpolation value at 80% conversion rate was derived. The results are shown in Table 24. Pt-B-MTT exhibits excellent selectivity for heavy products, low iso / normal ratio and good activity. This is one of the preferred choices.

Fischer-Tropsch Product Improvement This embodiment describes a preferred method for converting a Fischer-Tropsch product to a diesel fuel that combines superior yield and properties as compared to a conventional Fischer-Tropsch diesel fuel. .

  The product of the Fischer-Tropsch process consists in part of materials already in the diesel boiling range and in part heavier materials. In conventional processing, materials in the diesel boiling range are hydrotreated and then mixed into the diesel pool or used as is as a pool mix component. The heavy material is hydrocracked with an acidic catalyst to form an isoparaffin mixed component that is mixed with the first diesel material. Conventional hydrocracking produces isoparaffin over the entire boiling range of diesel. In this preferred embodiment, heavy material is converted to diesel range material by n-paraffin selective hydroconversion. Otherwise, the heaviest part of the diesel fuel that will have an unacceptable cloud point is isomerized. This gives a product with the maximum amount of normal paraffin. Since only the heaviest material is hydroisomerized, the amount of normal paraffin increases and the cetane number increases.

  In FIG. 1, synthesis gas (5) is fed to a slurry bed Fischer-Tropsch unit using a supported cobalt catalyst. The vapor phase product is removed from the reactor, cooled and the liquid concentrate (15) is recovered. The concentrate can be processed in an optional processor (20) to remove oxides and saturated olefins. The optional processor can be a conventional hydroprocessor using a non-acidic support, or an alumina processor. The latter converts oxides to olefins by dehydration. The Fischer-Tropsch process, which sends the treated concentrate (25) to a distillation facility (40) also produces a waxy product (16), which is converted to an n-paraffin selective hydroconversion reactor (30). To produce an effluent (35). Optionally, the waxy product (16) is first hydrotreated to remove impurities such as nitrogen, oxygen, olefins, solids, etc. in a reactor not shown. The hydroconversion reactor uses 10-ring borosilicate, preferably silica bonded Pt / B-ZSM-5 containing less than 20 ppm by weight of aluminum, 250 psig, 1 LHSV, and 70 percent conversion per treatment. Operates at a temperature that gives The effluent from the hydrocracker is also sent to the distillation facility. A light product or series of light products (42) is recovered from the distillation facility. Light products can be used as feedstock for ethylene production. Light diesel fuel consisting mainly of normal paraffin (45) is recovered. A heavy diesel fraction (46) is also recovered. The heavy diesel fraction is processed in a hydroisomerization dewaxing facility that converts heavy normal paraffin to isoparaffin. Isomerized heavy diesel fuel (52) is mixed with light diesel fuel to produce a mixed diesel (55) that meets cloud point specifications and has a cetane index greater than 60.

  Although this embodiment describes the production of diesel fuel, it is very similar to the equivalent embodiment for the production of jet fuel with adjustment of the product boiling range.

Improvement of Waxy Petroleum Product by Lubricating Base Oil Production This embodiment describes a preferred method for converting a waxy petroleum product to a lubricating base oil, along with the production of valuable normal paraffin-rich byproducts.

  Lubricating base oil is produced from petroleum products containing materials in the 650 ° F. + boiling range. 650 ° F containing waxy petroleum products such as hydrotreated petroleum streams, hydrocracked petroleum streams, hydroisomerized petroleum streams, and crude waxes are treated in a hydroconversion reactor to reduce normal paraffins in the feed to lighter normal It can be selectively converted to paraffin. Lighter normal paraffin can be separated from the unconverted product by distillation. Lighter normal paraffins can then be used to produce feedstocks for the production of solvents, jet fuel, jet fuel blend components, diesel fuel, diesel fuel blend components, and linear alkylbenzenes. The unconverted product, here at least partially devoid of normal paraffins, is converted to a lubricating base oil by a process comprising solvent dewaxing, catalytic dewaxing, hydrotreating, hydrocracking, solvent extraction and combinations thereof be able to. Catalytic dewaxing, especially hydroisomerization dewaxing, is preferred. In hydroisomerization dewaxing, waxy materials are isomerized with a catalyst to lower their pour point. The selectivity of normal paraffin during this isomerization treatment is lower than the selectivity of other compounds. This relatively low normal paraffin selectivity during processing results in the production of lighter products of lower value, typically including a mixture of normal and isoparaffins. By selectively converting normal paraffins in the feed to lighter products of valuable normal paraffins, the overall economy is improved. In FIG. 2, waxy 650 ° F. + petroleum feed (105), preferably crude wax, is processed in a hydroconversion reactor (130). The hydroconversion reactor uses 10-ring borosilicate, preferably silica bonded Pt / B-ZSM-5 containing less than 20 ppm by weight of aluminum, 250 psig, 1 LHSV, and 70 percent conversion per treatment. Operates at a temperature that gives The effluent from the hydrocracker (135) is also sent to the distillation facility (140). A light product or series of light products (142) is recovered from the distillation facility. The light product can be used as a feedstock for ethylene production, jet fuel, diesel fuel or linear alkylbenzene. A 650 ° F. unconverted portion (145) is recovered from the distillation facility. It is processed at the lubricating base oil production facility (150) to produce the lubricating base oil (155). Preferably, the lubricating base oil production facility comprises a catalytic hydroisomerization reactor that uses Pt on a 10-ring molecular sieve to isomerize residual waxy species in the unconverted product and lower the pour point to the desired value. Most preferably, the molecular sieve used in the hydroisomerization reactor is SAPO-11, ZSM-23 or SSZ-32. Hydroisomerization reactor conditions are 1000 psig, 1 LHSV, 5000 SCFB, and temperature to achieve the desired pour point. The lubricating base oil production facility also includes a distillation section for adjusting the viscosity and flash of the base oil product, and hydroprocessing equipment to reduce aromatic content and improve color and stability.

1 is a schematic diagram of a method for improving the Fischer-Tropsch product. FIG. 1 is a schematic diagram of a method for improving a waxy petroleum product from a lubricating base oil production. FIG.

Claims (49)

A hydrocarbon feed containing more than 5% by weight of C ₁₀₊ n-paraffins is converted in the presence of hydrogen to produce a product of n-paraffin having a lower molecular weight than C ₁₀₊ n-paraffins in the feed. For preparing said raw material a. The temperature is 600 to 800 ° F,
b. Pressure is 50 to 5000 psig,
c. (1) a borosilicate or aluminoborosilicate molecular sieve containing at least 0.05 wt% boron and less than 1000 ppm by weight of aluminum, or a titanosilicate molecular sieve, and (2) No. 8 By contacting with a catalyst comprising a group metal.   The method of claim 1, wherein the borosilicate or aluminoborosilicate molecular sieve contains less than 200 ppm by weight of aluminum.   The method of claim 1, wherein the borosilicate or aluminoborosilicate molecular sieve contains less than 20 ppm by weight of aluminum. C ₆ product has a iso / normal weight ratio of less than 0.2 The method of claim 1. The method of claim 1, wherein the C ₆ product has an iso / normal weight ratio of less than 0.05. The process of claim 1, wherein the C ₆ product has an iso / normal weight ratio of less than 0.01. The method of claim 1, wherein the product further comprises a C ₁₃ product having an iso / normal weight ratio of less than 2. The C ₁₃ product has the iso / normal weight ratio of less than 0.5 The method of claim 7. The C ₁₃ product has the iso / normal weight ratio of less than 0.1 The method of claim 7.   The method of claim 1, wherein the Group 8 metal is selected from the group consisting of Pt, Pd, Rh, Ir, Ru, Os, and combinations thereof.   The method of claim 10, wherein the Group 8 metal is Pt.   The method according to claim 10, wherein the amount of the metal is 0.1 to 5% by weight with respect to the weight of the molecular sieve.   The method according to claim 10, wherein the amount of the metal is 0.1 to 3% by weight with respect to the weight of the molecular sieve.   The method according to claim 10, wherein the amount of the metal is 0.3 to 1.5% by weight, based on the weight of the molecular sieve.   The method of claim 1, wherein the molecular sieve is zeolite.   The method according to claim 15, wherein the zeolite contains 12 or less pores and has a dimension number of 1 or more.   The method according to claim 16, wherein the pores have 10 rings or less and the number of dimensions is 2 or more.   The method according to claim 16, wherein the number of dimensions of the pores is 3 or more.   The zeolite is SSZ-13, SSZ-33, SSZ-46, SSZ-53, SSZ-55, SSZ-57, SSZ-58, SSZ-59, SSZ-60, SSZ-64, SSZ-70, ZSM- 16. The method of claim 15, selected from the group consisting of 5, ZSM-11, TS-1, MTT and HY.   20. A process according to claim 19, wherein the zeolite is ZSM-5.   The method of claim 1, wherein the raw material is selected from the group consisting of crude wax, Fischer-Tropsch product, and combinations thereof.   The method of claim 1, wherein the hydrocarbon feed contains less than 100 ppm each of sulfur and nitrogen.   2. The process of claim 1 wherein the catalyst has been exposed to sulfur prior to contacting the n-paraffin containing hydrocarbon feedstock. A hydrocarbon feed containing more than 5% by weight of C ₁₀₊ n-paraffins is converted in the presence of hydrogen to produce a lower molecular weight n-paraffin product than C ₁₀₊ n-paraffins in the feed. A method, wherein the raw material is
a. The temperature is 600 to 800 ° F,
b. Pressure is 50 to 5000 psig,
c. LHSV is 0.5 to 5,
d. Conversion from n-paraffin to smaller n-paraffin in the raw material is 25% to 99%
In contact with a catalyst comprising (1) a borosilicate or aluminoborosilicate molecular sieve containing at least 0.05% by weight boron and less than 1000 ppm by weight of aluminum, or a titanosilicate molecular sieve and (2) a Group 8 metal. And the selectivity for converting n-paraffin in the raw material to the smaller n-paraffin is 60% or more.   The method according to claim 24, wherein the selectivity is 80% or more.   The method according to claim 24, wherein the selectivity is 90% or more.   The method according to claim 24, wherein the selectivity is 95% or more.   25. The method of claim 24, wherein the borosilicate or aluminoborosilicate molecular sieve contains less than 200 ppm by weight of aluminum.   25. The method of claim 24, wherein the borosilicate or aluminoborosilicate molecular sieve contains less than 20 ppm by weight of aluminum. C ₆ product has a iso / normal weight ratio of less than 0.2 The method of claim 24. C ₆ product has a iso / normal weight ratio of less than 0.05 The method of claim 24. C ₆ product has a iso / normal weight ratio of less than 0.01 The method of claim 24. It said product further comprises a C ₁₃ product with less than 2 iso / normal weight ratio, The method of claim 24. The _{C 13} product has the iso / normal weight ratio of less than 0.5 The method of claim 33. The _{C 13} product has the iso / normal weight ratio of less than 0.1 The method of claim 33.   25. The method of claim 24, wherein the Group 8 metal is selected from the group consisting of Pt, Pd, Rh, Ir, Ru, Os, and combinations thereof.   38. The method of claim 36, wherein the Group 8 metal is Pt.   37. The method of claim 36, wherein the amount of metal is from 0.1 to 5% by weight based on the weight of the molecular sieve.   37. The method of claim 36, wherein the amount of metal is from 0.1 to 3% by weight based on the weight of the molecular sieve.   37. The method of claim 36, wherein the amount of metal is from 0.3 to 1.5% by weight based on the weight of the molecular sieve.   25. The method of claim 24, wherein the molecular sieve is zeolite.   42. The method of claim 41, wherein the zeolite contains 12 or fewer pores and has a dimension number of 1 or greater.   43. The method of claim 42, wherein the pores are 10 rings or less and the number of dimensions is 2 or more.   43. The method of claim 42, wherein the pore has a dimension number of 3 or more.   The zeolite is SSZ-13, SSZ-33, SSZ-46, SSZ-53, SSZ-55, SSZ-57, SSZ-58, SSZ-59, SSZ-60, SSZ-64, SSZ-70, ZSM- 42. The method of claim 41, selected from the group consisting of 5, ZSM-11, TS-1, MTT and HY.   46. The method of claim 45, wherein the zeolite is ZSM-5.   25. The method of claim 24, wherein the raw material is selected from the group consisting of crude wax, Fischer-Tropsch product, and combinations thereof.   25. The method of claim 24, wherein the hydrocarbon feed contains less than 100 ppm each of sulfur and nitrogen.   25. The method of claim 24, wherein the catalyst has been exposed to sulfur prior to contacting the n-paraffin containing hydrocarbon feed.

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